Cambridge S-series Direct Gas-fired Industrial Blow-thru Space Heater Technical Technical Manual

S-SERIES
DIRECT GAS-FIRED
INDUSTRIAL BLOW-THRU® SPACE HEATER
TECHNICAL MANUAL
mWARNING:
Improper installation, adjustment, alteration, service or maintenance can cause property
damage, injury or death. Read the installation, operating, and maintenance instructions
thoroughly before installing or servicing this equipment.
FOR YOUR SAFETY
The use and storage of gasoline or other flammable vapors and liquids in open containers
in the vicinity of this appliance is hazardous.
ASHRAE
FOR YOUR SAFETY
90.1
If you smell gas:
1. Open windows.
2. Don’t touch electrical switches.
3. Extinguish any open flame.
4. Immediately call your gas supplier.
Made in the USA
COMPLIANT
®
®
S-TM8-0120
S-SERIES
BLOW-THRU® SPACE HEATER
TECHNICAL MANUAL
LIMITED WARRANTY
Cambridge Air Solutions' Limited Warranty is included within the Terms and Conditions that are sent
with every Order Acknowledgement. For questions regarding Limited Warranty, contact Cambridge Air
Solutions' Customer Service Group at 1-800-473-4569.
Copyright © 2020
Cambridge Air Solutions
All Rights Reserved
Cambridge Air Solutions
760 Long Road Crossing Dr.
Chesterfield, MO. 63005
Phone: (636) 532-2233, (800) 899-1989
Fax: (636) 530-6133
www.cambridgeair.com
CONTENTS
Hazard Summary.................................................2
Vertical Inlet Skirt ....................................46
Accessory Identification..............................3
Unit Inlet Skirt..........................................48
Typical System Overview....................................3
Heater Operation.........................................5
Heater Configuration...................................5
Installation Instructions........................................6
Uncrating Instructions.................................6
Mounting Location......................................6
Roof Top Mounting Curb / Stand / Rail......................................7
Roof Top / Thru Wall Mounting Stand / Rail..................................................8
Under Roof Mounting - Curb.....................8
Roof Top Mounting.....................................9
Thru Wall Mounting.................................. 11
Roof Top / Thru Wall Mounting...............13
Under Roof Mounting...............................15
Vertical Indoor Mounting..........................17
Vertical Outdoor Mounting.......................19
Vertical S-Series
Structural Inlet Elbow...............................21
Vertical S-Series Structural
Non-Adjustable Elbow..............................25
Vertical S-Series Adjustable Stand............27
Vertical S-Series 3', 4', &5'
Duct Extensions........................................30
Vertical S-Series Adjustable Elbow..........32
Vertical S-Series Structural
Filter Section.............................................34
S-Series 24", 38", & 50"
Wall Sleeves..............................................37
S-Series Downturn With Lugs .................39
S-Series Upturn ........................................41
Horizontal S-Series 4’
Mounting Stand ........................................43
Rain Hood Inlet Skirt ...............................47
Gas Piping.................................................49
Electrical Wiring ......................................50
Remote Control Station and Temperature
Sensor Locations.......................................51
Thermistor Sensor.....................................53
Start-Up Instructions..........................................54
Calibration Procedures ......................................60
Operating Instructions........................................63
Operating Sequence..................................63
Electronic Thermostat...............................64
TSS Controller .........................................66
Bacnet Controller......................................75
Maintenance Instructions...................................79
Troubleshooting Instructions.............................83
Troubleshooting Guide.............................83
Damper Motor Replacement
& Adjustment............................................89
Reference...........................................................91
Electrical Control Enclosure
Isometric Drawing....................................91
Electrical Wiring Diagrams ......................92
Remote Control Station Electrical
Connection Diagram ................................97
Building Automation System....................98
Gas Train Drawings..................................99
Individual Component
Descriptions............................................103
ANSI/ASHRAE/IESNA
Standard 90.1..........................................109
Maintenance Log............................................. 110
QR Code.......................................................... 113
HAZARD SUMMARY
Hazard Identification
Warnings and Cautions appear at appropriate sections throughout this manual. Read these carefully.
mWARNING:Indicates a potentially hazardous situation which could result in
death or serious injury.
mCAUTION:
Indicates a potentially hazardous situation which may result in
minor or moderate injury. It may also be used to alert against
unsafe practices.
CAUTION:
Indicates a situation that may result in accidents with equipment or
property damage only.
If the heater is installed such that an inlet duct is
utilized, the duct system must be purged with at least
four air changes prior to an ignition attempt.
The following safety precautions apply to the
installation, operation, and maintenance of the
equipment described by this technical manual.
Installation in Aircraft Hangars
Refer to the Standard for Aircraft Hangars,
ANSI/NFPA 409, for specific information on
the installation requirements for these heaters in
aircraft hangars.
mWARNING:
Any unauthorized modification of this equipment
shall void the warranty.
mWARNING:
Only qualified personnel should attempt
installation, service, and repair of this equipment.
Use extreme caution and observe safety
regulations at all times.
Installation in Parking Garages
Refer to the Standard for Parking Structures,
ANSI/NFPA 88A, or the Standard for Repair
Garages, ANSI/NFPA 88B, for specific
information on the installation requirements for
these heaters in public garages.
mWARNING:
Recirculation of room air is not permitted.
Installation in Car Wash Facilities
A non-recirculating, S-Series Space Heater used in
a Car Wash tunnel application may be designated
as a T-Series Heater on the nameplate.
Adequate building relief must be provided so as to not
over pressurize the building when the heating system
is operating at its rated capacity. It should be noted
that this can be accomplished by taking into account,
through standard engineering methods, the structure’s
designed infiltration rate, by providing properly sized
relief openings, or by interlocking a powered exhaust
system, or by a combination of these methods.
This S-Series Technical Manual also applies to all
T-Series Heaters.
IMPORTANT
If in doubt regarding installation application, contact
Cambridge Customer Service Group at 1-800-4734569 during the hours of 8:00 a.m. to 5:00 p.m.
Central Time, Monday through Friday.
If the failure or malfunction of this heater creates
a hazard to other fuel burning equipment in the
building, (e.g. when the heater is providing the makeup air to a boiler room), the unit is to be interlocked to
open inlet air dampers or other such devices.
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S-Series Technical Manual
TYPICAL SYSTEM OVERVIEW
ACCESSORY IDENTIFICATION
Under Roof Mounting
IP
Roof Top Mounting
RH-RT
UNIT
MC
DT
MDD
ID
DT
MDD
AMS
MC
MR
DD
IE
UNIT
DE
DE
Thru Wall Mounting
RH-TW
Outdoor Vertical Mounting
WALL SLEEVE
(BY OTHERS)
DT
MDD
DT
DT
MDD
DE
FS
UNIT
ISR
UNIT
DE
Roof Top / Thru Wall Mounting
RH-RT
UNIT
MDD
WALL SLEEVE
(BY OTHERS)
DT
DE
AMS
ISU
MR
Indoor Vertical Mounting
DT
Component Identification
AMS
DD
DE
DT
FS
ID
IE
IP
ISR
ISU
MC
MDD
MR
RH-RT
RH-TW
Adjustable Mounting Stand
Discharge Duct
Directional Elbows
Downturn
Filter Section
Inlet Duct
Inlet Elbow
Inlet Plenum
Inlet Skirt-Rain Hood
Inlet Skirt-Unit
Mounting Curb
Motorized Discharge Damper
Mounting Rail
Rain Hood-Roof Top
Rain Hood-Thru Wall
S-Series Technical Manual
DT
DE
UNIT
RH-TW
IE
ISR
3
Cambridge Air Solutions
TYPICAL SYSTEM OVERVIEW
ACCESSORY IDENTIFICATION
ADJUSTABLE
ELBOW
WALL
SLEEVE
DOWNTURN
DUCT
EXTENSION
DIRECTIONAL
ELBOWS
DUCT
EXTENSION
RAINHOOD
FILTER
SECTION
UPTURN
HORIZONTAL
MOUNTING
STAND
FILTER
SECTION
SUPPORT
DOWNTURN
DOWNTURN
DUCT
EXTENSION
DOWNTURN
DIRECTIONAL
ELBOWS
DOWNTURN
STRUCTURAL
FILTER
SECTION
RAINHOOD
WALL
SLEEVE
DIRECTIONAL
ELBOWS
STRUCTURAL
INLET
ELBOW
RAINHOOD
ADJUSTABLE
STAND
EXTENSION
ADJUSTABLE
STAND
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S-Series Technical Manual
TYPICAL SYSTEM OVERVIEW
HEATER OPERATION
Cambridge S-Series Blow-Thru® heaters are utilized
to meet the space heating requirements of commercial
or industrial buildings. The control system is typically
designed to cycle the heaters on and off in response to
the rise and fall of the space temperature. The heater
will discharge air at the temperature selected (up to
160ºF). The operating thermostat is typically located
near the perimeter of the building in a location which
is out of the direct path of the heated discharge air,
insulated from cold surfaces, and shielded from cold
drafts created by air infiltrating the building.
HEATER CONFIGURATION
IGNITER & FLAMEROD
BURNER ASSEMBLY
DAMPER MOTOR
DISCHARGE TEMPERATURE SENSOR
HIGH LIMIT
DAMPER BLADES
ELECTRICAL
CONTROL ENCLOSURE
HINGED ACCESS DOOR
PORT FOR MEASURING
MANIFOLD PRESSURE
MODULATING GAS VALVE
SAFETY SHUT-OFF VALVE
LEAK TEST PORT
SHUT-OFF VALVE
DISCHARGE AIR TEMPERATURE
SAMPLING BOX
REGULATOR
MANUAL SHUT-OFF VALVE
S-Series Technical Manual
BURNER VIEWPORT
5
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
UNCRATING INSTRUCTIONS
1. Verify that the number of items on the Bill of
Lading matches the number of items received.
It is the responsibility of the installer to communicate
any potential problems with the installation to
the person or persons responsible for providing
the installation instructions or drawings prior to
proceeding with the installation.
2. Check for shipping damage. Take photographs of
any damage.
IMPORTANT
If damage is found, immediately file a claim with the
carrier before proceeding further.
IMPORTANT
Where the mounting height of the heater is a
consideration, work platforms or service lifts should
be provided for accessibility to the equipment for
service and maintenance activities.
3. Check the items received to make sure they agree
with the ordering information including verification
of data on the unit nameplate.
IMPORTANT
Field constructed intake accessories should be
designed to minimize the entry of snow and rain.
IMPORTANT
Do not discard any components or accessories.
IMPORTANT
The minimum clearance from the face of the
electrical control enclosure to surrounding
grounded surfaces for service activities is 42”.
Adequate clearance of 42” for burner removal is
also required. Access for service functions is also
required on the side of the unit opposite the control
enclosure for a distance of 24”.
MOUNTING LOCATION
Verify feasibility of the installation location selected
with respect to accessibility to the heater for service
and maintenance functions. Ensure the positioning
of the heater does not inhibit fork truck operation,
storage rack locations, or other operations within
the facility. Ensure the heater inlet and outlet are not
blocked or severely restricted in any way that would
affect the rated airflow through the heater or affect the
desired air distribution pattern of the heater.
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S-Series Technical Manual
INSTALLATION INSTRUCTIONS
ROOF TOP MOUNTING - CURB / STAND / RAIL
STAND DETAIL
NOTES
1
TREATED
TIMBER AS REQUIRED UNDER MOUNTING
CURB, RAIL AND STAND TO SECURE AND LEVEL UNIT.
SECOND
MOUNTING ASSEMBLY IS REQUIRED ONLY ON
UNITS WITH FILTER SECTIONS.
MOUNTING
STAND CONSTRUCTION:
12 GA. GALVANIZED STEEL
2
3
SECURE MOUNTING STAND TO TIMBER WITH WOOD LAG
SCREWS AS SHOWN.
6
7
10½"
4
5
6
2 x 6 TREATED LUMBER
(BY OTHERS)
7
MOUNTING RAIL CONSTRUCTION:
18 GA. GALVANIZED STEEL
REMOVE
HANGER BRACKET AND REPLACE SCREWS
ADJUSTABLE
± 3¾”
DOWNTURN / CURB
WITH FLASHING
24"
REF.
ROOF INSULATION
2
24"
TYP.
C
MOUNTING STAND
1
MOUNTING RAIL
4
5
A
B
2 X 6 TREATED LUMBER
CURB SECTION
3
FLASHING
2 x 2 WOOD NAILER
(PROVIDED)
INSULATION
Model
A
B
C
S400/S800
65½”
33¼”
25 3/8”
S950/S1200/S1600
78 5/8”
33¼”
42”
S1850/S2200/S3200
90¼”
36¼”
47 1/8”
S-Series Technical Manual
2.5"
7
1 5/8"
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
ROOF TOP / THRU WALL MOUNTING - STAND / RAIL
STAND DETAIL
NOTES
1
TREATED
TIMBER AS REQUIRED UNDER MOUNTING RAIL
AND STAND TO SECURE AND LEVEL UNIT.
2
3
SECURE MOUNTING STAND TO TIMBER WITH WOOD LAG
SCREWS AS SHOWN.
THIRD MOUNTING ASSEMBLY IS REQUIRED ONLY ON
UNITS WITH FILTER SECTIONS.
6
7
10½"
4
MOUNTING
STAND CONSTRUCTION:
12 GA. GALVANIZED STEEL
5
6
2 x 6 TREATED LUMBER
(BY OTHERS)
7
MOUNTING RAIL CONSTRUCTION:
18 GA. GALVANIZED STEEL
REMOVE
HANGER BRACKET AND REPLACE SCREWS
STAND
IS ADJUSTABLE ±3¾”
ROOF INSULATION
2
24"
TYP.
C
MOUNTING STAND
1
MOUNTING RAIL
4
5
A
B
2 X 6 TREATED LUMBER
3
Model
A
B
C
S400/S800
57 7/8”
33¼”
25 3/8”
S950/S1200/S1600
69 7/8”
33¼”
42”
S1850/S2200/S3200
75¾”
36¾ ”
47 1/8”
UNDER ROOF MOUNTING - CURB
CURB SECTION
CURB
24"
REF.
2 x 2 WOOD NAILER
(PROVIDED)
INSULATION
2.5"
1 5/8"
ROOF INSULATION
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S-Series Technical Manual
INSTALLATION INSTRUCTIONS
ROOF TOP MOUNTING
installed so that the heater will mount level.
Cambridge recommends mounting the heater a
minimum of 24” off the roof surface in areas where
snow accumulation could impact heater operations.
mWARNING:
Due to the size and weight of this equipment, it
is recommended the heater mounting structure
be reviewed and approved by a qualified
structural engineer and the roof manufacturer
before installing this equipment.
3. Attach the mounting stands to the heater while the
heater is on the ground. Adjust the height of the
stands so the heater inlet is slightly (1/8” below
level) lower than the discharge. This allows any
ingested moisture to drain out of the heater, through
weep holes located at the inlet of the heater, onto
the roof surface.
IMPORTANT
Before proceeding with the installation, verify the
feasibility of the location selected with respect to
accessibility for service and maintenance functions.
4. Lower the discharge duct through the mounting
curb and the roof opening and secure the
counterflashing to the mounting curb.
IMPORTANT
To minimize snow and rain ingestion, position the
heater inlet opposite the prevailing winds.
5. Use a crane or comparable lifting device to raise
and position the equipment. Use a spreader bar to
prevent damage and connect slings to the lifting
brackets.
mCAUTION
To prevent contaminated air from being drawn
into the heater, install the heater’s inlet at least
10 feet from any building exhaust, process
exhaust, sewer stacks, or other sources that
would allow contaminants to be drawn into
the heater. Consult local codes for additional
references.
mWARNING:
Do not attach lifting means to heater accessories.
Make connections to heater only.
IMPORTANT
Inlet accessories may be attached on the ground or
on the roof depending on the method chosen by the
installer.
1. Prepare
roof penetration to the dimensions below.
See page 6 for Roof Top Mounting - Curb/Stand/
Rail drawing.
6. Caulk all the joints between the heater and the
accessories with silicone caulk to prevent water
leaks.
IMPORTANT
Accurate measurements are critical and will affect
the installation process. Verify that the roof opening
aligns with the curb opening.
IMPORTANT
Do not caulk the downturn/counterflashing for the
curb interface.
2.Secure the mounting curb and mounting rail(s) per
the structural engineer and roof manufacturer’s
recommendations.
7. S
eal all roof penetrations to prevent roof leaks.
8. I nstall the directional elbows. Consult the job
layout for the orientation of the elbows.
IMPORTANT
The roof curb and mounting rail(s) should be
Roof Opening*
Model
S400/S800
Weight
L
W
550 lbs.
13”
24¾”
S950/S1200/S1600
800 lbs.
15”
41½”
S1850/S2200/S3200
1500 lbs.
24¼”
46½”
S-Series Technical Manual
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Cambridge Air Solutions
TYPICAL INSTALLATION
ROOF TOP MOUNTING
RAIN HOOD
FILTER SECTION
(OPTIONAL)
UNIT
DOWNTURN
ADJUSTABLE MOUNTING STAND
NOTE:
DO NOT CAULK
THIS JOINT
MOUNTING RAIL
ELECTRICAL CONTROL ENCLOSURE
COUNTERFLASHING
MOUNTING CURB
ELECTRICAL JUNCTION BOX
(PROVIDED WITH EXTERNAL GAS TRAIN)
DISCHARGE DUCT
EXTERNAL GAS TRAIN WITH ENCLOSURE
(APPLICABLE TO SOME FM AND XL GAPS OPTIONS)
DIRECTIONAL
ELBOWS
FM: FACTORY MUTUAL
XL GAPS: FORMERLY IRI (INDUSTRIAL RISK INSURERS)
CURB / RAIL / STAND DETAIL
2 X 6 TREATED LUMBER
(BY OTHERS)
10½"
24"
2 X 4 TREATED LUMBER
(PROVIDED)
TREATED LUMBER
(BY OTHERS)
12"
TREATED LUMBER
(BY OTHERS)
ROOF
OPENING
TREATED LUMBER (THICKNESS OF ROOF INSULATION) AS
REQUIRED UNDER MOUNTING STANDS AND CURB TO SECURE
AND LEVEL THE UNIT AND TO SPREAD THE LOAD. (BY OTHERS)
* Dimensions allow for ¾” clearance on each side
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S-Series Technical Manual
INSTALLATION INSTRUCTIONS
THRU WALL MOUNTING
5.Use a forklift or comparable lifting device to
raise and position the heater. Take precautions
to prevent equipment damage (dents and/or
scratches) when the heater is being lifted into
position.
mWARNING:
Due to the size and weight of this equipment, it
is recommended the heater mounting structure be
reviewed and approved by a qualified structural
engineer before installing this equipment.
6.Use washers and double lock nuts to secure the
unit on the hanging rods.
IMPORTANT
Before proceeding with the installation, verify the
feasibility of the location selected with respect to accessibility to the equipment for service and maintenance functions.
IMPORTANT
The discharge end of the heater should be raised
slightly (1/8” above level). This allows any ingested
moisture to drain out of the heater through weep
holes located in the rain hood to the exterior of the
building.
mCAUTION
To prevent contaminated air from being drawn into
the heater, install the heater’s inlet at least 10 feet
from any building exhaust, process exhaust, sewer
stacks, or other sources that would allow contaminants to be drawn into the heater. Consult local
codes for additional references.
7.Apply shims, by others, at the bottom of the rain
hood to take up slack in the opening, leaving a
small joint between the top of the rain hood and
the wall.
8.Install fiberglass insulation in the gaps around the
wall opening and the rain hood. Apply enough
material to accommodate the full thickness of the
wall.
1.Prepare wall penetration to the dimensions below.
2.Connect inlet accessories to the unit including
filter section (optional) and rain hood prior to lifting the heater in place. Note the inlet skirt for rain
hood (optional) is installed from the outside of the
building (page 20).
9.Install finish trim pieces (by others) to the top,
sides and bottom of the rain hood on both the
inside and outside wall surfaces.
10.Apply silicone caulk at the joint between the top
of the rain hood and the outside wall surface.
Make certain this is a continuous bead and that it
runs the entire width of the rain hood. Caulk all
other exposed joints.
3.Install hanging rods to adequate ceiling supports
and align with the hanging brackets on the unit.
Refer to hanging rod size shown on table below.
Locate the hanging rods so that the weep holes
provided in the rain hood are located a minimum
of 3” beyond the outside wall surface.
11.Install the directional elbows. Consult the job
layout for the orientation of the elbows.
4.Remove the lag bolts used to fasten the unit to the
skid. Do not remove the hanging brackets from the
side of the heater. On S400/S800 model heaters,
rotate the mounting brackets 180˚ and retighten the
securing hardware.
Hanging Rods
Wall Opening**
Model
S400/S800
Weight
Qty.
Size
A
B*
C
H
W
550 lbs.
4 (6*)
3/8” dia.
57 7/8”
33¼”
27 7/8”
26”
25½”
S950/S1200/S1600
800 lbs.
4 (6*)
3/8” dia.
69 7/8”
33¼”
43 7/8”
29”
42¼”
S1850/S2200/S3200
1500 lbs.
4 (6*)
1/2” dia.
75¾”
36¾”
48 7/8”
38¾”
47¼”
*For optional filter section
** Dimensions allow for 1” clearance on each side
S-Series Technical Manual
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Cambridge Air Solutions
TYPICAL INSTALLATION
THRU WALL MOUNTING
FILTER SECTION
(OPTIONAL)
RAINHOOD
UNIT
HANGING ROD
(BY OTHERS)
EXTERIOR WALL TRIM
(BY OTHERS)
INTERIOR WALL TRIM
(BY OTHERS)
DOWNTURN
ELECTRICAL CONTROL ENCLOSURE
INCOMING POWER
VENT w/SCREEN
(LOCATE MIN. 10 FT. FROM INTAKE)
DIRECTIONAL
ELBOWS
INLET GAS PIPE
VENT PIPE TO OUTDOORS
(BY OTHERS)
HANGING BRACKET
CONTROL WIRING CONDUIT
(BY OTHERS)
LOW PRESSURE SHUT-OFF VALVE
HIGH PRESSURE REGULATOR (HPR)
HIGH PRESSURE SUPPLY TAP
REMOTE CONTROL STATION
(OPTIONAL)
HIGH PRESSURE SHUT-OFF VALVE
SEDIMENT TRAP
(BY OTHERS)
HANGING BRACKET DETAIL
HANGING ROD
NUT
WASHER
WASHER
DOUBLE LOCK NUTS
SHIPPING POSITION
HANGING ROD DETAIL
HANGING ROD
NUT
WASHER
WASHER
DOUBLE LOCK NUTS
HANGING RODS, NUTS AND WASHERS BY OTHERS
L BRACKET
FOR S400 - S800 UNITS
Cambridge Air Solutions
C BRACKET
FOR S950 - S3200 UNITS
12
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
ROOF TOP / THRU WALL MOUNTING
3. Attach the mounting stands to the heater while
the heater is on the ground. Adjust the height
of the stands so the heater inlet is slightly (1/8”
below level) lower than the discharge. This allows
any ingested moisture to drain out of the heater,
through weep holes located at the inlet of the heater, onto the roof surface.
mWARNING:
Due to the size and weight of this equipment, it
is recommended the heater mounting structure be
reviewed and approved by a qualified structural
engineer and the roof manufacturer before
installing this equipment.
4. Use a crane or comparable lifting device to raise
and position equipment. Use a spreader bar to
prevent damage and connect slings to the lifting
brackets.
IMPORTANT
Before proceeding with the installation, verify the feasibility of the location selected with respect to accessibility to the equipment for service and maintenance
functions.
mWARNING:
Do not attach lifting means to heater accessories.
Make connections to heater only.
IMPORTANT
To minimize snow and rain ingestion, position the
heater inlet opposite the prevailing winds.
IMPORTANT
Inlet accessories may be attached on the ground or
on the roof depending on the method chosen by the
installer.
mCAUTION
To prevent contaminated air from being drawn
into the heater, install the heater’s inlet at least 10
feet from any building exhaust, process exhaust,
sewer stacks, or other sources that would allow
contaminants to be drawn into the heater. Consult
local codes for additional references.
5. Install the wall sleeve to the heater discharge.
6. Install fiberglass insulation in gaps around the wall
opening and wall sleeve. Apply enough material to
accommodate the full thickness of the wall.
1. Prepare wall penetration to the dimensions below.
See page 7 for Roof Top/Thru Wall Mounting
Stand/Rail drawing.
7. Install finish trim pieces (by others) to top, sides
and bottom of the wall sleeve on both the inside
and outside wall surfaces.
IMPORTANT
Accurate measurements are critical and will affect
installation process.
8. Apply silicone caulk at the joint between the top
of the wall sleeve and the outside wall surface.
Make certain this is a continuous bead and that it
runs the entire width of the wall sleeve. Caulk all
other exposed joints.
2.Secure the mounting rails per the structural
engineer and roof manufacturer’s
recommendations.
IMPORTANT
The mounting rails should be installed so that the
heater will mount level. Cambridge recommends
mounting the heater a minimum of 24” off the roof
surface in areas where snow accumulation could
impact heater operations
9. Seal all roof penetrations to prevent roof leaks.
10.Install the downturn and directional elbows.
Consult the job layout for the orientation of the
elbows.
Wall Opening*
Model
S400/S800
Weight
H
W
550 lbs.
16”
28¼”
S950/S1200/S1600
800 lbs.
18”
45”
S1850/S2200/S3200
1500 lbs.
27½”
50”
S-Series Technical Manual
13
Cambridge Air Solutions
TYPICAL INSTALLATION
ROOF TOP / THRU WALL MOUNTING
RAIN HOOD
FILTER SECTION
(OPTIONAL)
UNIT
WALL SLEEVE
EXTERIOR WALL TRIM
(BY OTHERS)
ADJUSTABLE MOUNTING STAND
INTERIOR WALL TRIM
(BY OTHERS)
MOUNTING RAIL
ELECTRICAL CONTROL ENCLOSURE
DOWNTURN
DIRECTIONAL
ELBOWS
ELECTRICAL JUNCTION BOX
(PROVIDED WITH EXTERNAL GAS TRAIN)
EXTERNAL GAS TRAIN WITH ENCLOSURE
(APPLICABLE TO SOME FM AND XL GAPS OPTIONS)
STAND DETAIL
2 X 6 TREATED LUMBER
(BY OTHERS)
2 X 4 TREATED LUMBER
(PROVIDED)
10½"
12"
TREATED LUMBER
(BY OTHERS)
* Dimensions allow for 1½” clearance on each side
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S-Series Technical Manual
INSTALLATION INSTRUCTIONS
UNDER ROOF MOUNTING
IMPORTANT
The mounting curb or mounting structure should
be installed such that the heater’s inlet plenum will
mount level.
mWARNING:
Due to the size and weight of this equipment, it
is recommended the heater mounting structure be
reviewed and approved by a qualified structural
engineer and the roof manufacturer before
installing this equipment.
3. Seal all roof penetrations to prevent roof leaks.
4.Lower the inlet duct through the mounting curb
and the roof opening.
IMPORTANT
Before proceeding with the installation, verify the
feasibility of the location selected with respect to accessibility to the equipment for service and maintenance functions.
5. Secure the inlet plenum to the curb.
6.Connect inlet accessories to the heater including
filter section (optional) and inlet elbow prior to
lifting the heater in place.
m CAUTION
7.Install hanging rods to adequate ceiling supports
and align with the hanging brackets on the heater.
Refer to hanging rod size shown on table below.
To prevent contaminated air from being drawn
into the heater, install the heater’s inlet at least 10
feet from any building exhaust, process exhaust,
sewer stacks, or other sources that would allow
contaminants to be drawn into the heater. Consult
local codes for additional references.
8.Remove the lag bolts used to fasten the unit to the
skid. Do not remove the hanging brackets from the
side of the heater. On S400/S800 model heaters,
rotate the hanging brackets 180˚, and retighten the
securing hardware.
1.Prepare roof penetration to the dimensions below.
See page 7 for Under Roof Mounting - Curb drawing
9.Use a forklift or comparable lifting device to
raise and position the heater. Take precautions
to prevent equipment damage (dents and/or
scratches) when the heater is being lifted into
position.
IMPORTANT
Accurate measurements are critical and will affect
the installation process. Verify that the roof opening
aligns with the curb opening.
10.Use washers and double lock nuts to secure
equipment on the hanging rods.
2.Install the mounting curb and the mounting structure per the structural engineer and roof manufacturer’s recommendations.
11.Install the directional elbows. Consult the job
layout for the orientation of the elbows.
Hanging Rods
Roof Opening**
Model
S400/S800
Weight
Qty.
Size
A
B*
C
L
W
550 lbs.
4 (6*)
3/8” dia.
57 7/8”
33¼”
27 7/8”
25”
25”
S950/S1200/S1600
800 lbs.
4 (6*)
3/8” dia.
69 7/8”
33¼”
43 7/8”
30”
41¼”
S1850/S2200/S3200
1500 lbs.
4 (6*)
1/2” dia.
75¾”
36¾”
48 7/8”
37¼”
46¾”
*For optional filter section
** Dimensions allow for ¾” clearance on each side
S-Series Technical Manual
15
Cambridge Air Solutions
TYPICAL INSTALLATION
UNDER ROOF MOUNTING
CURB DETAIL
FILTER SECTION (OPTIONAL)
TREATED LUMBER (THICKNESS OF ROOF INSULATION) AS
REQUIRED UNDER MOUNTING CURB TO SECURE AND LEVEL
THE UNIT AND TO SPREAD THE LOAD. (BY OTHERS)
HANGING BRACKET DETAIL
HANGING ROD
NUT
WASHER
WASHER
DOUBLE LOCK NUTS
SHIPPING POSITION
HANGING ROD DETAIL
HANGING ROD
NUT
WASHER
WASHER
DOUBLE LOCK NUTS
HANGING RODS, NUTS AND WASHERS BY OTHERS
L BRACKET
FOR S400 - S800 UNITS
Cambridge Air Solutions
C BRACKET
FOR S950 - S3200 UNITS
16
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
VERTICAL INDOOR MOUNTING
4.Remove the lag bolts used to fasten the unit to the
skid. Rotate the hanging brackets for the vertical
application and retighten the securing hardware.
mWARNING:
Due to the size and weight of this equipment, it
is recommended the heater mounting structure be
reviewed and approved by a qualified structural
engineer before installing this equipment.
5.Utilizing the lifting brackets on the front of the heater,
use a forklift or comparable lifting device to raise
and position the heater. Take precautions to prevent
equipment damage (dents and/or scratches) when the
heater is being lifted into position.
IMPORTANT
Before proceeding with the installation, verify the
feasibility of the location selected with respect to accessibility to the equipment for service and maintenance functions.
6.Use washers and double lock nuts to secure
equipment on hanging rods.
IMPORTANT
The rain hood should be sloped slightly (1/8” off
level). This allows any ingested moisture to drain out
of the heater through weep holes located in the rain
hood to the exterior of the building.
m CAUTION
To prevent contaminated air from being drawn
into the heater, install the heater’s inlet at least 10
feet from any building exhaust, process exhaust,
sewer stacks, or other sources that would allow
contaminants to be drawn into the heater. Consult
local codes for additional references.
7.Apply shims at the bottom of the rain hood to take up
slack in the opening, leaving a minimal joint between
the top of the rain hood and the wall.
1.Prepare wall penetration to the dimensions below.
8.Install fiberglass insulation in the gaps around the
wall opening and the rain hood. Apply enough
material to accommodate the full thickness of the
wall.
2.Connect the inlet accessories to the heater including
the filter section (optional), the inlet elbow and the
rain hood prior to standing the heater upright. Note
the inlet skirt for the rain hood (optional) is installed
from the outside of the building (page 20).
9.Install finish trim pieces (by others) to the top, sides
and bottom of the rain hood on both the inside and
outside wall surfaces.
3.Install hanging rods to adequate ceiling and/or wall
supports per the structural engineer’s recommendations and align with the hanging brackets on the
heater. Refer to the hanging rod size shown on the
table below. Locate the hanging rods so that the
weep holes provided in the rain hood are located a
minimum of 3” beyond the outside wall surface.
10.Apply silicone caulk at the joint between the top
of the rain hood and the outside wall surface.
Make certain this is a continuous bead and that it
runs the entire width of the rain hood. Caulk all
other exposed joints.
11.Install the second downturn and directional
elbows. Consult the job layout for the orientation
of the elbows.
Hanging Rods
Wall Opening*
Model
Weight
Qty.
Size
A
B
H
W
S400/S800
650 lbs.
4
3/8” dia.
23 3/8”
27 7/8”
26”
25½”
S950/S1200/S1600
950 lbs.
4
3/8” dia.
26”
43 7/8”
29”
42¼”
S1850/S2200/S3200
1750 lbs.
4
1/2” dia.
34 7/8”
48 7/8”
38¾”
47¼”
S-Series Technical Manual
17
Cambridge Air Solutions
TYPICAL VERTICAL INDOOR INSTALLATION
STRUCTURAL
KNEE BRACE
(BY OTHERS)
DOWNTURN
SECOND DOWNTURN
(OPTIONAL)
GAS TRAIN WIRING
(FIELD CONNECTED)
mWARNING:
DIRECTIONAL
ELBOWS
The primary structural support
element of a vertically mounted
heater is the base. Any support
to the heater cabinet should be
considered secondary, only as a
means to help stabilize the heater.
GAS TRAIN
HANGING ROD
(BY OTHERS)
UNIT
BASE OF HEATER
ELECTRICAL CONTROL
ENCLOSURE
FILTER SECTION
(OPTIONAL)
HANGING ROD DETAIL
INLET ELBOW
SECOND DOWNTURN
(OPTIONAL)
DOWNTURN
INTERIOR WALL TRIM
(BY OTHERS)
EXTERIOR WALL TRIM
(BY OTHERS)
RAIN HOOD
HANGING BRACKET DETAIL
HANGING RODS, NUTS AND WASHERS BY OTHERS
SHIPPING POSITION
SHIPPING POSITION
HANGING ROD
NUT
WASHER
HANGING ROD
NUT
WASHER
WASHER
DOUBLE LOCK NUTS
WASHER
DOUBLE LOCK NUTS
MOUNTING POSITION
MOUNTING POSITION
C BRACKET
FOR S950 - S3200 UNITS
L BRACKET
FOR S400 - S800 UNITS
* Dimensions allow for 1” clearance on each side
Cambridge Air Solutions
18
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
VERTICAL OUTDOOR MOUNTING
7. Install the wall sleeve to the downturn.
mWARNING:
8.Install fiberglass insulation in the gaps around the
wall opening and the wall sleeve. Apply enough
material to accommodate the full thickness of the
wall.
Due to the size and weight of this equipment, it
is recommended the heater mounting structure be
reviewed and approved by a qualified structural
engineer before installing this equipment.
9.Install finish trim pieces (by others) to the top,
sides and bottom of the wall sleeve on both the
inside and outside wall surfaces.
IMPORTANT
Before proceeding with the installation, verify the
feasibility of the location selected with respect to accessibility to the equipment for service and maintenance functions.
10.Apply silicone caulk at the joint between the wall
sleeve and the outside wall surface. Make certain
this is a continuous bead and that it runs the entire
width of the wall sleeve. Caulk all other exposed
joints.
mCAUTION
To prevent contaminated air from being drawn
into the heater, install the heater’s inlet at least 10
feet from any building exhaust, process exhaust,
sewer stacks, or other sources that would allow
contaminants to be drawn into the heater. Consult
local codes for additional references.
11.Mount the gas train enclosure to the wall structure
and connect gas piping between the heater and the
enclosure.
12.Install the inlet skirt to the heater inlet and attach
the skirt extension to the exterior wall (page 21).
1. Prepare wall penetration to the dimensions below.
13.Install wall sleeve, second downturn and
directional elbows. Consult the job layout for the
orientation of the elbows.
2.Connect the inlet accessories to the heater including the filter section (optional).
3.Install structural uprights and associated wall supports per structural engineers recommendations.
4.Remove the lag bolts used to fasten the unit to the
skid.
5.Utilizing the lifting brackets on the front of the
heater, use a forklift or comparable lifting device
to raise and position the heater. Take precautions to prevent equipment damage (dents and/or
scratches) when the heater is being lifted into position.
6.Secure the heater in place with contractor supplied
hardware.
* Dimensions allow for 1½” clearance on each side
S-Series Technical Manual
19
Cambridge Air Solutions
TYPICAL VERTICAL OUTDOOR INSTALLATION
INTERIOR WALL FLASHING
(BY OTHERS)
WALL SLEEVE
EXTERIOR WALL FLASHING
(BY OTHERS)
SECOND DOWNTURN
(OPTIONAL)
DOWNTURN
DIRECTIONAL
ELBOWS
GAS TRAIN WIRING
(FIELD CONNECTED)
UNIT
GAS TRAIN ENCLOSURE
mWARNING:
GAS TRAIN
The primary structural support
element of a vertically mounted
heater is the base. Any support
to the heater cabinet should be
considered secondary, only as a
means to help stabilize the heater.
ELECTRICAL CONTROL ENCLOSURE
BASE OF HEATER
FILTER SECTION
(OPTIONAL)
INLET SKIRT
(FIELD ASSEMBLED)
CHANNEL SUPPORT
(BY OTHERS)
MOUNTING DETAIL
SECURE STRUCTURAL CHANNEL
TO WALL (AS REQUIRED)
(BY OTHERS)
DOWNTURN
BUILDING WALL
BUILDING FOOTING
Cambridge Air Solutions
20
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES STRUCTURAL INLET ELBOW
Ceiling-Mounted
brackets (4 plcs)
Stand-Mounted
brackets (4 plcs)
Ceiling-Mounted
Floor-Mounted
Stand-Mounted
Floor-Mounted
Retaining clip
Retaining clip
Structural
inlet elbow
Structural
inlet elbow
Retaining clip
(downblast
Retaining clip
(downblast
Structural
inlet elbow
Structural
inlet elbow
Structural
inlet elbow
Structural
inlet elbow
Airflow
Airflow
The vertical S-Series structural inlet elbow is suitable for indoor or outdoor use. The elbow has been structurally
reinforced to support the weight of the unit and any additional accessories applicable to your installation. It can be
used in floor-mounted applications, with or without a stand, as well as ceiling-mounted applications when hanging
the unit with threaded rod. The elbow is insulated to prevent condensation and reduce noise levels.
Model
Weight
A
B
C
S400/S800
150 lbs.
27 1/2”
25 3/8”
25 3/8”
S950/S1200/S1600
205 lbs.
30 3/4”
28”
42”
S1850/S2200/S3200 300 lbs.
40 3/8”
37 3/8”
47 1/8”
A
A
C
B
B
S-Series Technical Manual
C
21
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES STRUCTURAL INLET ELBOW
6. Secure threaded rod to ceiling structure as needed.
CEILING-MOUNTED APPLICATIONS
1. Remove the accessory mounting brackets from the top
of the inlet elbow and reattach them on the bottom of
the inlet elbow for hanging.
7. Double-nut the end of the rod below the mounting
bracket at the bottom of the inlet elbow.
Accessory
Accessory
Accessory
bracket
Accessory
bracket
bracket
bracket
8. It is recommended to run support back to the wall to
prevent swaying or tipping of heater and accessories.
2. If heater is vertical downblast, remove the retaining
clip and attach to the opposite flange. .
• Use the provided holes in the mounting brackets to
run threaded rod (by others) to support on walls (by
others).
3. Use the included heater mounting brackets to attach
the inlet elbow to the heater (or filter section if
applicable).
• If filter section is included, attach heater to filter
sec-tion using provided accessory mounting brackets
after inlet elbow and filter
section are connected.
Heater
Ø 5/8” holes for
wall support
Ø 5/8”
holes
forfor
Ø 5/8”
holes
Ø 5/8”
holes for
wall
support
wall support
wall support
Heater
Heater
bracket
Heater
bracket
bracket
bracket
Bolts
Lock washers
Bolts
Bolts
Structural
Boltsinlet elbow
Lock
washers
Lock
washers
Lockinlet
washers
Structural
elbow
Structural inlet
elbow
Structural inlet elbow
9. For indoor installations, attach thru-wall rain hood and
inlet skirt if applicable.
4. If not already attached, secure elbow to discharge of
heater using provided heater mounting brackets.
5. Position heater with attached accessories upright and
lift into place.
Cambridge Air Solutions
22
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES STRUCTURAL INLET ELBOW
5. It is recommended to run support back to the wall to
prevent swaying or tipping of heater and accessories.
STAND-MOUNTED APPLICATIONS
1. Once the stand is set, attach inlet elbow to stand using
the provided accessory mounting brackets.
• Use the provided holes in the mounting brackets to
run threaded rod (by others) to support on walls (by
others).
Structural inlet
Structural inlet
elbowStructural inlet
elbow
Accessory
elbow
Accessory
Accessory
bracket
bracket
bracket
Adjustable stand
Adjustable stand
Adjustable stand
Ø 5/8” holes for
Ø 5/8” holes for
wall
support
Ø wall
5/8”
holes for
support
wall support
Bolt
Bolt
Lock washer
Bolt
Lock washer
Lock washer
2. I f filter section included, attach filter section to
inlet elbow using the provided accessory mounting
brackets. If filter section is not included, skip to
step 3.
6. For indoor installations, attach thru-wall rain hood and
inlet skirt if applicable.
3. A
ttach heater to inlet elbow (or filter section) below
using the provided heater mounting
Heater brackets.
Heater
Heater
bracket
bracket
bracket
Bolts
Bolts
Bolts
Lock washers
Lock washers
Structural inlet
elbow
Lock
washers
Structural inlet elbow
Structural inlet elbow
4. C
ontinue attaching discharge accessories with
provided mounting brackets as needed.
S-Series Technical Manual
23
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES STRUCTURAL INLET ELBOW
9. Continue attaching discharge accessories to heater as
needed using the provided mounting brackets.
FLOOR-MOUNTED APPLICATIONS
1. Remove the mounting brackets from the top of the
inlet elbow and reattach them on the bottom of the
inlet elbow for anchoring to the floor.
Heater
Heater
Heater
bracket
Heater
bracket
bracket
bracket
Bolts
Boltswashers
Lock
Bolts
Lock
washers
Structural
inlet
elbow
Bolts
Lock inlet
washers
Structural
elbow
Lock washers
Structural inlet elbow
Structural inlet elbow
10. It is recommended to run support back to the wall to
prevent swaying or tipping of heater and accessories.
• Use the provided holes in the mounting brackets to
run threaded rod (by others) to support on walls (by
others).
2. Determine the distance needed between the building
wall and the heater.
3. Place inlet elbow where desired and mark anchor locations using holes in the attached mounting brackets.
11. For indoor installations, attach thru-wall rain hood
and inlet skirt if applicable.
4. Install wedge anchors, minimum 0.5”x6” (not
provided), as recommended by manufacturer into
concrete floor where marked.
5. Set inlet elbow over anchors.
6. Make sure inlet elbow is level using shims (by others)
if necessary.
7. Once level, secure elbow to anchors with washer and
lock nut (not provided).
applicable) to inlet
8. Attach heater (or filter section if bracket
bracket
elbow using the provided mounting
brackets.
Anchor
lock nut
Ø 5/8” holes for
Ø 5/8”
for
wall holes
support
wall
support
Ø 5/8” holes for
Ø 5/8”
holes for
wall support
wall support
Anchor lock nut
bracket
Washer
bracketlock nut
Anchor
Washer
Installed
anchor
Anchor lock
nut
Washer
Installed anchor
Washer
Installed anchor
Installed anchor
Cambridge Air Solutions
24
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES NON-ADJUSTABLE ELBOW
Retaining clip
brackets (Qty 2)
Non-adjustable elbows
Retaining clip
brackets (Qty 2)
Non-adjustable elbows
Non-adjustable
elbows
Non-adjustable
elbows
Airflow
ment plates
Airflow
ment plates
The non-adjustable elbow is suitable for discharge ductwork to turn air 90° for either indoor or outdoor S-Series
installations. It attaches to the discharge end of a vertical heater or vertical duct extensions with 4 accessory
mounting brackets (shipped with the heater or vertical duct extension) that can either be suspended via threaded
hanging rod or secured horizontal to the wall in stand mounted applications. The discharge end of the elbow attaches
easily to wall sleeves or downturns with lugs. directional elbows with a discharge collar can also be attached directly
to the non-adjustable elbow if desired. Non-adjustable elbows are insulated to help mitigate noise and thermal losses.
Model
Weight
A
B
C
S400/S800
45 lbs.
13”
25 3/8”
25 3/8”
S950/S1200/S1600
75 lbs.
15”
28”
42”
S1850/S2200/S3200
130 lbs.
24 5/8”
37 1/2”
47”
A
Airflow
A
C
B
B
S-Series Technical Manual
Airflow
C
25
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES NON-ADJUSTABLE ELBOW
1. Prepare the non-adjustable elbow for assembly by
re moving the bolts and washers from the sides.
For ceiling mounted applications please refer to the
installation instructions for the structural inlet elbows.
5a. If attaching a wall sleeve or a downturn with lugs,
secure it using both the retaining clip and side
attachment plates. Follow additional installation steps
detailed in the appropriate accessory installation
instructions.
Non-adjustable
elbowelbow
Non-adjustable
Non-adjustable
elbow
Wall Wall
sleeve
sleeve
Non-adjustable elbow Wall sleeve
Wall sleeve
Non-adjustable elbow
Wall sleeve
2. Prepare the upstream accessory or heater by removing
the accessory mounting brackets.
3. Lift the non-adjustable elbow into place and secure it
plates
mentplates
plates
using the bolts and washers removed in the previousmentment
step.
ment plates
Non-adjustable
Non-adjustable
Non-adjustable
elbowelbow
elbow
Non-adjustable
elbow
Accessory
Accessory
Accessory
Accessory
bracket
bracket
bracket
ment plates
5b. If attaching a discharge collar and directional elbows
replace the screws removed in step 4. Attach the
dis-charge collar to the discharge face of the nonadjustable elbow and secure using self-tapping
Non-adjustable
elbowelbow
Non-adjustable
Non-adjustable
elbow
screws. Arrange the
directional
elbows
in the desired
configu-ration before securing
them
to
the
discharge
Non-adjustable elbow
collar.
Non-adjustable
elbow
bracket
Accessory
Non-adjustable elbow
bracket
Heater
Heater
Heater
4. If not already done, remove the side attachment
Heater plates
from the discharge end of the non-adjustable elbow. If
attaching a discharge collar with directional elbows,
Heater
also remove the retaining clip.
Retaining
clip clip
Retaining
Retaining
clip
Non-adjustable
Non-adjustable
Non-adjustable
elbowelbow
elbow
Non-adjustable
elbow
Discharge
collarcollar
Discharge
Discharge
collar
Retaining clip
Discharge collar
Retaining clip
Non-adjustable
elbow
Discharge collar
6. Seal all seams between heater and accessories
using appropriate contractor grade caulk to mitigate
ment plates
potential water ingestion and pressure loss.
mentment
plates
mentplates
plates
Heater
Heater
Heater
ment plates
Heater
Cambridge Air Solutions
Heater
26
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES ADJUSTABLE STAND
Inlet screen
Inlet screen
Height adjustment
label (2/leg)
48”-54”
Height adjustment
label (2/leg)
48”-54”
Adjustable
stand
(4 plcs)
Adjustable
stand
(4 plcs)
The Vertical S-Series Adjustable Stand is suitable for use in the up blast configuration in both indoor and outdoor
locations. The 48” height is low enough so the control can may still be accessible without lifts or ladders, but high
enough to avoid snow ingestion from the ground during winter months. The stand features 6” of adjustment (up to
54”) and is suitable for applica-tions when you prefer the heater to be easily accessible for service, yet floor space or
slab size may come at a premium.
1. Determine distance needed between building wall and
heater (12” recommended).
Parts List
•O
uter edge of template matches footprint of vertical
unit and
stand w/ centerline of heater indicated.
Template Detail
E
Template Detail
E
Centerline
A
Anchor center
Centerline
CA
Sonotube
center
Anchor
center
C
Sonotube center
D
B
D
B
S-Series Technical Manual
Item
Description
Qty.
1
Adjustable stand (assembled)
1
2
Template
1
3
Leveling shims
20
F
F
Heater/Stand
Footprint
Anchor
Locations (o)
Sonotube
Locations (+)
Stand
Size
Weight
S400/
S800
176 lbs. 25 1/2” 25 1/2” 16 3/4” 16 3/4” 19 7/8” 19 7/8”
S950/
S1200/
S1600
196 lbs.
S1850/
S2200/
S3200
222 lbs. 37 1/2”
27
A
28”
B
C
D
E
F
42”
19 1/2” 33 1/2” 36 1/2” 22 1/2”
47”
28 7/8” 38 1/2” 41 5/8”
32”
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES ADJUSTABLE STAND
2. Use provided template to mark anchor locations on
existing concrete slab. Consult structural engineer as
to adequacy of existing slab for structural support.
• If no slab available, installation of sonotubes with
housekeeping pad is recommended. Use template to
mark center locations of sono-tubes (indicated with
”+” cutout).
• Install sonotubes as recommended by struc-tural
engineer and use template to mark an-chor locations
(indicated with ”o” hole) on sonotubes.
AnchorAnchorAnchorholes
holes
holes
Template
Template
Centerline
Template
Centerline
SonotubeCenterline
SonotubeSonotubecutouts
cutouts
cutouts
Drilled holes for
Drilledanchors
holes for
Drilled holes for
anchors
anchors
• If shimming necessary, insert provided shims where
needed to level the stand.
• Once level and square, secure base to anchors with
washer and lock nut (not provided).
• Shims are NOT intended to be used for ad-justing
the overall stand height. See next step.
Stand leg
Stand leg
Stand leg
Anchor lock nut
Anchor lock nut
Washer
Anchor
lock nut
Washer
Washer
Stand shim
Stand shim
Stand shim
8. Determine if default stand height (48”) is correct for
heater installation.
• If adjustment needed, remove height adjust-ment
bolts (2/leg), and raise stand necessary amount using
the height label as a guide.
Concrete slab
Concrete slab
Concrete slab
3. Once concrete/sonotubes are marked, remove and
discard template.
• Reattach height adjustment bolts.
4. Drill holes for anchors.
Washer
Washer
Height
Washer
Height
adjustment
Height
adjustment
bolt (2/leg)
adjustment
bolt (2/leg)
bolt (2/leg)
5. Set stand over anchor locations.
6. Install outdoor rated wedge anchors, minimum
0.5”x6” (not provided), as recommended by
manufacturer into concrete slab/sonotubes where
marked.
Cambridge Air Solutions
7. Make sure stand is both level and square.
28
Nut
Lock
Nut washer
Nut
Lock
washer
Lock
Heightwasher
label
Height label
Height label
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES ADJUSTABLE STAND
9. Set heater (or structural filter section, or structural inlet elbow if applicable) on stand and attach appropriate
mounting brackets, securing to the stand using the provided bolts and lock washers.
• I f structural filter section or structural inlet elbow included, attach heater to top of inlet accessory using included mounting brackets and hardware.
Heater
Heater
Structural
inlet elbow
Structural
inlet elbow
3/8” Bolts and
lock washers
3/8” Bolts and
lock washers
Accessory
Heater
Accessory
bracket
(4 plcs)
bracket
(4 plcs)
Heater
bracket
(4 plcs)
bracket
(4 plcs)
10. If provided, assemble angled inlet skirt pieces and attach to stand using self-drilling screws (not provided).
Attach close-off panel to stand and skirt on side nearest wall using self-drilling screws (not provided).
Self-drilling
screws
Self-drilling
screws
Inlet skirt
Inlet skirt
Skirt close-off
panel
Skirt close-off
panel
S-Series Technical Manual
29
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES 3’, 4’, & 5’ DUCT EXTENSIONS
Accessory
Horizontal Mounted
Accessory
Horizontal Mounted
brackets (Qty 4)
brackets (Qty 3’
4) duct
extension
4’ duct
extension
Airflow
3’ duct
extension
4’ duct
extension
5’ duct
extension
5’ duct
extension
Airflow
The vertical S-Series duct extensions (3’, 4’, & 5’) are suitable for horizontal pad mount and vertical up blast
configurations in both indoor and outdoor locations. The different duct sizes allow for combinations to achieve
different desired discharge heights. All ducts come with four mounting brackets which can be used for rigging,
securing the duct to other accessories, and securing the duct work to the building structure. All ducts are insulated
with 1” fiberglass insulation to mitigate thermal losses and reduce vibrations and noise.
Heater Size
S400/S800
Airflow
Airflow
S950/S1200/S1600
A
A
S1850/S2200/S3200
B
B
C
Cambridge Air Solutions
Duct
Weight
A
B
C
3’
95 lbs.
36”
25 3/8”
25 1/4”
4’
135 lbs.
48”
25 3/8”
25 1/4”
5’
160 lbs.
60”
25 3/8”
25 1/4”
3’
120 lbs.
36”
28 1/8”
42”
4’
165 lbs.
48”
28 1/8”
42”
5’
200 lbs.
60”
28 1/8”
42”
3’
140 lbs.
36”
37 1/2”
47 1/8”
4’
200 lbs.
48”
37 1/2”
47 1/8”
5’
240 lbs.
60”
37 1/2”
47 1/8”
C
30
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES 3’, 4’, & 5’ DUCT EXTENSIONS
1. Remove the mounting brackets from the top of the
already installed upturn or duct extension. If mounting
on top of the unit, remove any remaining lifting
brackets.
3. Continue attaching discharge accessories to the
configuration as needed using the provided mounting
brackets.
4. It is recommended to run support back to the wall to
prevent swaying or tipping of heater and accessories.
• Use the provided holes in the mounting brackets to
run threaded rod (by others) to support on walls (by
others).
Duct extension
or upturn
Duct
extension
Duct
extension
Duct
extension
or
upturn
upturn
oror
upturn
Ø 5/8” holes for
wall support
2. P
lace the ductDuct
extension
on top of the existing
extension
installation and use the provided brackets to secure
them together.
bracket
Ø 5/8”
holes
for
5/8”
holes
ØØ
5/8”
holes
forfor
wall
support
wall
support
wall
support
Duct
extension
Duct
extension
Duct
extension
bracket
Bolts
bracket
bracket
Lock washers
bracket
bracket
bracket
bracket
Duct extension Bolts
Bolts
Bolts
or upturn
Lock
washers
Lock
washers
Lock
washers
Duct
extension
Duct
extension
Duct
extension
or
upturn
upturnDuct extension
oror
upturn
bracket
Duct
extension
Duct
extension
Duct
extension
Bolts
bracket
bracket
bracket
Lock washers
bracket
bracket
bracket
bracket
S-Series Technical Manual
Heater Bolts
Bolts
Bolts
Lock
washers
Lock
washers
Lock
washers
Heater
Heater
Heater
31
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES ADJUSTABLE ELBOW
(Qty. 2)
Horizontal Outdoor
Adjustable
elbow
(Qty. 2)
Adjustable
elbow
Horizontal Outdoor
Adjustable
elbow
Adjustable
elbow
plates (Qty. 2)
Airflow
The adjustable elbow is suitable for discharge ductwork to turn air 90° for either indoor or outdoor vertical S-series
plates
(Qty. 2) end of vertical duct extensions with a slip fit that allows its height to be
installa-tions. It attaches to
the discharge
Airflow
adjusted from 0-6”. The discharge end of the elbow can attach easily to wall sleeves where the height adjustability
allows for an easier alignment of the wall sleeve with the wall hole. Downturns with lugs or directional elbows
with a discharge collar can also be attached directly to the adjustable elbow if needed in indoor applications. This
accessory cannot directly attach to an unit due to its in-terference with the heater’s gas train. Adjustable elbows are
insulated to help mitigate noise and thermal losses.
Model
Weight
A
B
C
S400/S800
55 lbs.
20 1/2”
25 1/2”
25 1/2”
S950/S1200/S1600
85 lbs.
22 5/8”
28 1/4”
42 1/4”
S1850/S2200/S3200
140 lbs.
32 1/4”
37 5/8”
47 1/4”
A
A
C
B
B
Cambridge Air Solutions
C
32
S-Series Technical Manual
Duct extension
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES ADJUSTABLE ELBOW
Adjustable
Elbow
1. Prepare the upstream accessory (the vertical duct
extension) by removing the accessory mounting
bracket.
Duct
extension
Duct
extension
Adjustable
plates
elbow
Adjustable
elbow
2. L
ift the adjustable elbow into place on top of the duct
extenstion. Adjust the height of the elbow to the
Duct
desired height and secure the elbow to the vertical
extension
duct exten-sion using the provided self tapping screws.
If the elbow is raised to a height which allows the
bolt holes used in step 1 to become exposed, replace
and tighten the re-moved bolts and washers to help
mitigate potential wa-ter ingestion and pressure loss.
Adjustable
elbow
Adjustable
elbow
Wall sleeve
Wall sleeve
4a. If attaching a wall sleeve or a downturn with lugs,
secure it using both the retaining clip and side
attachment plates. Follow additional installation steps
detailed in the appropriate accessory installation
instructions.
Adjustable
elbow
Side
Duct
extension
Wall
sleeve
Duct extension
Side
Wall
sleeve
Wall
sleeve
Duct extension
Duct extension
Adjustable
elbow
Retaining Clip
Side
Duct extension
4b. If attaching a discharge collar and directional elbows
replace the removed screws that were securing the
side attachment plates. Attach the discharge collar to
the discharge face of the adjustable elbow and secure
using self-tapping screws. Arrange the directional
elbows in the desired configuration before securing
them to the discharge collar.
3. I f not already
done, remove the side attachment
Retainingplates
Clip
Adjustable
from the discharge end of the adjustable elbow. If
Elbow
Wall
attaching
a discharge collar with directional
elbows,
Retaining
Clip
Adjustable
sleeve
also remove the retaining clip.
Elbow
5. Seal all seams between accessories using appropriate
contractor grade caulk to mitigate potential water
ingestion and pressure loss.
Duct extension
plates
plates
S-Series Technical Manual
Adjustable
Elbow
Retaining Clip
33
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES STRUCTURAL FILTER SECTION
brackets (Qty 4)
Indoor Up Blast
Indoor Down Blast
Outdoor Up Blast
Structural
Structural
Airflow
The Structural Filter Section is designed to be used with any S-Series vertical installation (indoor/outdoor, up/down
blast). It designed to be load bearing and can support the weight of the unit with all necessary additional ductwork. It
is designed with a set of doors on both sides to ensure that it can never be installed backwards. It can either be hung
from the ceiling or mounted on top of the 4’ adjustable mounting stand or structural inlet elbow with 4 accessory
mounting brackets. It is capable of using permanent, disposable, or MERV-13 filters. All Structural Filter Sections
are insulated and double skinned to help mitigate con-densation, noise, and thermal losses.
Airflow
Model
Weight
A
B
C
S400/S800
150 lbs.
30 3/8”
25 3/8”
25 3/8”
S950/S1200/S1600
175 lbs.
25 3/8”
28”
42”
S1850/S2200/S3200
235 lbs.
30 3/8”
37 1/8”
47”
A
Filters
B
Cambridge Air Solutions
Model
C
34
Quantity
Dimensions
S400/S800
2
20” x 25” x 2”
S950/S1200/S1600
4
20” x 25” x 2”
S1850/S2200/S3200
12
16” x 25” x 2”
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES STRUCTURAL FILTER SECTION
3. Attach all additional accessories following appropriate
installation instructions.
MOUNTING STAND OR STRUCTURAL
INLET ELBOW MOUNTING APPLICATIONS
1. Lift the structural filter section into place on top of
the adjustable mounting stand or structural inlet elbow
and remove the 4 accessory mounting brackets from
the discharge end of the structural filter section. Fasten
them together securely using the 4 accessory mounting
brackets.
brackets (Qty 4)
brackets
(Qty
4)4)
brackets
(Qty
4. It is recommended to run support back to the wall to
prevent swaying or tipping of heater and accessories.
• Use the provided holes in the mounting brackets to
run threaded rod (by others) to support on walls (by
others).
Structural filter
Structural
filter
Structural
filter
Ø 5/8” holes for
wall support
ØØ
5/8”
holes
forfor
5/8”
holes
wall
support
wall support
5. Seal all seams between accessories using appropriate
contractor grade caulk to mitigate potential water
ingestion and pressure loss.
Adjustable
Adjustable
Adjustable
2. L
ift the heater into place and secure by using 4 of the
heater mounting brackets.
Heater
Heater
Heater
brackets
(Qty 4)
brackets
brackets
(Qty
4)4)
(Qty
Heater
Heater
Heater
Structural
Structural
Structural
Accessory
Accessory
Accessory
brackets
(Qty 4)
brackets
brackets
(Qty
4)4)
(Qty
S-Series Technical Manual
Adjustable
Adjustable
Adjustable
stand
stand
stand
35
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
VERTICAL S-SERIES STRUCTURAL FILTER SECTION
CEILING-MOUNTED APPLICATIONS
1. Remove the heater mounting brackets from the
heater and all accessory mounting brackets from all
necessary accessories (structural inlet elbow, structural
filter sec-tion, vertical duct extensions, adjustable inlet
elbow, and non-adjustable inlet elbow).
3. After having the configuration assembled, carefully
lift entire assembled configuration into place and
secure to the ceiling using threaded rod as directed by
structural engineers.
4. Double nut the end of the rod below the lowest
mounting bracket.
2. Use the removed mounting brackets to attach the
heat-er and all previously mentioned accessories
together. This should be done in a manner to ensure
that only the structural filter section, structural inlet
elbow , or heater bears the load as the vertical duct
extensions, adjustable elbow, and non-adjustable
elbow are all non-load bearing accessories. This likely
means that the unit configuration should be assembled
horizontally.
Structural inlet elbow
Accessory
Non-adjustable
elbow
Non-adjustable
Non-adjustable
elbow
elbow
Structural
elbow
Structural
inletinlet
elbow
Accessory
Accessory
5. It is recommended to run support back to the wall to
prevent swaying or tipping of heater and accessories.
brackets (Qty 8)
• Use the provided holes in the mounting brackets to
run threaded rod (by others) to support on walls (by
others).
brackets
brackets
(Qty(Qty
8) 8)
Heater
Heater
Heater
Ø 5/8” holes for
wall support
Ø 5/8”
holes
Ø 5/8”
holes
for for
support
wallwall
support
Structural filter
Structural
Structural
filterfilter
6. Attach thru-wall rain hood and all additional
accessories.
7. Seal all seams between accessories using appropriate
contractor grade caulk to mitigate potential water
ingestion and pressure loss.
Structural inlet
elbow
Structural
Structural
inletinlet
elbow
elbow
brackets
brackets
brackets
Cambridge Air Solutions
36
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
S-SERIES 24”, 38”, & 50” WALL SLEEVES
Retaining clip
Airflow
Horizontal Mounted
24” wall sleeve
38” wall sleeve
50” wall sleeve
plates (Qty 2)
The S-Series wall sleeves (24”, 38”, and 50”) are suitable for discharge duct work for either vertical or horizontal
configurations. They are designed to be attached at its inlet side by a retaining clip and two side brackets. The
discharge end is designed to hold either additional accessories by the same method (a retaining clip and two side
brackets) or a set of directional elbows and discharge collar. All wall sleeves are insulated to help mitigate noise and
thermal losses.
Heater Size
S400/S800
Airflow
S950/S1200/S1600
A
S1850/S2200/S3200
C
S-Series Technical Manual
Sleeve Weight
A
B
C
24”
35 lbs.
13”
25 3/8”
24”
38”
50 lbs.
13”
25 3/8”
38”
50”
65 lbs.
13”
25 3/8”
50”
24”
50 lbs.
15”
42”
24”
38”
75 lbs.
15”
42”
38”
50”
95 lbs.
15”
42”
50”
24”
60 lbs.
24 1/8”
47”
24”
38”
90 lbs.
24 1/8”
47”
38”
50”
115 lbs.
24 1/8”
47”
50”
B
37
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
S-SERIES 24”, 38”, & 50” WALL SLEEVES
1. After preparing the wall by cutting the appropriately
sized hole, prepare the upstream accessory (either
the adjustable or non-adjustable discharge elbow) by
removing the side attachment plates.
2. Slide the wall sleeve through the wall opening and
attach the inlet side of the wall sleeve to the upstream
accessory by use of it’s retaining clip. Reattach the
side attachment plates removed in step 1 and use self
tapping screws to secure the wall sleeve.
Retaining clip
clip
Retaining
Non-adjustable
Non-adjustable
elbow
elbow
Non-adjustable
Non-adjustable
elbow
elbow
Retaining
clip clip
Retaining
5a. If attaching a downturn with lugs, secure it using
both the retaining clip and side attachment plates.
Support the downturn by attaching threading rods
to the lugs as noted in the installation sheet for the
Downturn with Lugs.
Retaining clip
Wall Sleeve
Sleeve
Wall
Flashing by
by
Flashing
WallWall
Sleeve
Sleeve
others
others
Flashing
by
Flashing by
others
others
Retaining clip
Retaining
clip clip
Retaining
Wall sleeve
sleeve
Wall
WallWall
sleeve
sleeve
ment plate
plate
ment
mentment
plateplate
3. Use the appropriate framing techniques to frame, insulate, and flash the hole through which the wall sleeve
is protruding.
4. If not already done, remove the side attachment plates
from the discharge end of the wall sleeve. If attaching
a discharge collar with directional elbows, also
remove the retaining clip.
Downturn
Downturn
with lugs
lugs
with
Downturn
Downturn
withwith
lugs lugs
5b. If attaching a discharge collar and directional elbows
replace the removed screws that were securing the
side attachment plates. Attach the discharge collar to
the discharge face of the wall sleeve and secure using
self tapping screws. Arrange the directional elbows
in the desired configuration before securing them to
the discharge collar.
Wall sleeve
sleeve
Wall
WallWall
sleeve
Flashing
sleeve
Flashing
by
others
by others
Flashing
Flashing
by others
by others
Wall sleeve
sleeve
Wall
Flashing Wall sleeve
Flashing
Wall sleeve
by others
others
by
Flashing
Flashing
by others
by others
Retaining clip
clip
Retaining
Discharge
Discharge
collar
collar
Discharge
Discharge
collar
collar
elbows
elbows
elbows
elbows
Retaining
clip clip
Retaining
ment plate
plate
ment
mentment
plateplate
Cambridge Air Solutions
38
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
S-SERIES DOWNTURN WITH LUGS
Lugs (Qty. 2)
Downturn
w/lugs
Downturn
w/lugs
Airflow
Downturn
w/lugs
The S-Series downturn with lugs is suitable for discharge ductwork to turn air 90° for either vertical or horizontal
S-Series in-stallations. It is designed to be attached at its inlet side to a retaining clip and two side brackets on the
upstream accessory (either a wall sleeve or a discharge elbow). The discharge end is designed to hold a discharge
collar with directional elbows. The lugs are designed to be secured to the ceiling via threaded hanging rod.
Downturns with lugs are insulated to help mitigate noise and thermal losses.
Model
Weight
A
B
C
S400/S800
35 lbs.
25 1/4”
13”
S950/S1200/S1600
70 lbs.
28”
S1850/S2200/S3200
125 lbs.
28”
Mtg. Dimensions
D
E
25 3/8”
6 1/8”
28”
15”
42”
7 3/8”
44 5/8”
24 1/2”
47”
12 3/8”
49”
Top View
E
A
D
C
Inlet
B
S-Series Technical Manual
39
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
S-SERIES DOWNTURN WITH LUGS
1. Prepare the upstream accessory (wall sleeve,
adjustable elbow, or non adjustable elbow) by
removing the side attachment plates.
Wall sleeve
Wall sleeve
Wall sleeve
Hanging rod
Hanging rod Wall sleeve
Hanging rod
Wall sleeve
Wall sleeve
Wall sleeve
Hanging rod
Wall sleeve
Downturn
Downturn
Downturn
w/lugs
w/lugs
w/lugs
Downturn
5. If attaching a discharge collar and w/lugs
directional elbows:
Attach the discharge collar to the discharge face of
the downturn with lugs and secure using self tapping
screws. Arrange the directional elbows in the desired
configuration before securing them to the discharge
collar.
2. Lift the downturn with lugs into place and secure
it using the using both the retaining
clip
and side
Wall
sleeve
Wall sleeve
attachment plates.
Wall sleeve
Wall sleeve
Downturn
Downturn
Downturn
w/lugs
w/lugs
w/lugs
Downturn
Discharge
w/lugs
Discharge
Discharge
collar
collar
collar
Discharge
collar
ment plates
ment plates
ment plates
ment plates
elbows
elbows
elbows
elbows
Downturn
Downturn
Downturn
w/lugs
w/lugs
w/lugs
Downturn
w/lugs
3. Secure threaded hanging rod to the ceiling as required
by structural engineer.
6. Seal all seams between accessories using appropriate
contractor grade caulk to mitigate potential water
ingestion and pressure loss.
4. Secure threaded hanging rod to downturn with lugs
Cambridge Air Solutions
40
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
S-SERIES UPTURN
bracket (Qty. 4)
Horizontal Mount
Airflow
Upturn
The S-Series upturn is suitable for supporting vertical discharge ductwork after turning airing 90° upward from a
horizontal mounted unit. It is designed to be secured to the unit with the unit’s retaining bracket and the upturn’s
threaded PEM studs. The vertical duct extensions are designed to be attached to the upturn with 4 accessory
mounting brackets. Upturns are insu-lated to help mitigate noise and thermal losses.
A
B
S-Series Technical Manual
C
Model
Weight
A
B
C
S400/S800
75 lbs.
26 5/8”
25 3/8”
25 3/8”
S950/S1200/S1600
115 lbs.
29 1/4”
28”
42”
S1850/S2200/S3200
175 lbs.
38 1/2”
37 1/2”
47 1/4”
41
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
S-SERIES UPTURN
1. Prepare the upturn by removing the nuts and washers
from the threaded PEM studs on the front face of the
upturn.
4. Lift the duct extension into place and secure it with
the accessory mounting brackets removed in the
previous step.
Duct extension
Duct extension
Upturn
Upturn
Upturn
Heater
Heater
Duct extension
Heater
Duct extension
Upturn
Heater
2. Lift the upturn into place on top of the 4’ stand,
being sure to catch the lip of the upturn on the unit’s
retaining clip. Replace the washers and nuts removed
from step 1 onto the threaded PEM studs now inside
of the unit and tighten securely.
Upturn
Upturn
brackets
brackets
Upturn
brackets
Upturn
brackets
5. It is recommended to run support back to the wall to
prevent swaying or tipping of heater and accessories.
Use the provided mounting brackets to run threaded
rod (by others) to support on walls (by others).
Heater
Heater
Heater
Heater
Ø 5/8”Ø holes
for for
5/8” holes
wall support
Ø wall
5/8”support
holes for
wall support
Ø 5/8” holes for
wall support
4’ horizontal
4’ horizontal
standstand
Upturn
Upturn
6. Seal all seams between accessories using appropriate
contractor grade caulk to mitigate potential water
ingestion and pressure loss.
4’ horizontal stand
Upturn
on the
3. Remove the accessory mounting brackets
upturn in preparation to attach the duct extension.
4’ horizontal stand
Upturn
brackets
brackets
Heater
Heater
brackets
Heater
brackets
Heater
Upturn
Upturn
Upturn
Cambridge Air Solutions
Upturn
42
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
HORIZONTAL S-SERIES 4’ MOUNTING STAND
Horizontal Mounted
brackets (Qty 4)
support
The horizontal S-Series mounting stand is suitable for outdoor pad mounted configurations. The 48” height is ideal
for easy maintenance access while still remaining high enough to avoid potential snow ingestion from the ground
during winter months. It is designed to be installed perpendicular to the building and includes room for both the unit
and upturn to be situ-ated on the frame. Additional support legs are provided if a filter section is ordered.
Footprint Detail
Parts List
B
Leg base
A
12”sonotube
12” sonotube center
2 1/2”
1
4’ mounting stand (assembled)
1
2
Leveling shims
20
• 2 additional support legs, brace, and fasteners are
also included when ordering a Filter Section with
a horizontal mounting stand
• The anchors’ mounting locations are centered on
the 12” sonotubes
S400/S800
Qty.
Note:
Note:
Stand Size
Description
C
Heater footprint
2 1/2”
D
Weight (lbs.)
(w/F.S. supports)
Item
Stand Footprint
Anchor/Sonotube
Locations
A
B
C
D
330
25 3/8”
85 3/8”
20 1/4”
80 1/8”
S950/S1200/S1600
370
42”
100 1/8”
36 7/8”
95”
S1850/S2200/S3200
400
47”
117 1/2”
41 7/8”
112 3/8”
S-Series Technical Manual
43
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
HORIZONTAL S-SERIES 4’ MOUNTING STAND
1. Determine distance needed between building wall
and mounting stand/vertical duct extensions (12”
recommended).
6. Remove heater mounting brackets from stand.
2. Mark anchor locations on existing concrete slab.
Consult structural engineer as to adequacy of existing
slab for structural support.
brackets
7. Set heater on stand and secure using the heater
mounting brackets removed in the previous step.
• If no slab available, installation of sonotubes with
housekeeping pad is recommended. Use provided
dimensions on previous page to mark center
locations of sonotubes.
brackets
• Install sonotubes as recommended by struc-tural
engineer. Anchors should be centered on 12”
sonotubes.
Heater
3. Drill holes for anchors, clean out debris
from holes
and set stand over holes.
Heater
4. Install outdoor rated wedge anchors, minimum
0.5”x6” (not provided), as recommended by manufacturer into concrete slab/sonotubes where marked.
5. Make sure stand is both level and square.
brackets
• If shimming necessary, insert provided
shims where
needed to level the stand.
brackets
• Once level and square, secure base to anchors with
washer and lock nut (not provided).
• Shims are NOT intended to be used for ad-justing
the overall stand height.
Stand leg
Anchor lock nut
Stand leg
Anchor lock nut
Washer
Washer
Stand shim
Stand shim
Cambridge Air Solutions
44
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
HORIZONTAL S-SERIES 4’ MOUNTING STAND
bracket
Only complete the following steps if installing a filter
section:
10. Using the 2 additional filter section support legs,
bracket
brace,
and provided fasteners to secure the filter
section to the mounting stand legs at the inlet side.
8. I f attached, remove mounting bracket from filter
section. Any filters inside of the unit will need to be
removed before the next step to provide access to
internal mounting flange.
11. Seal all seams between accessories using appropriate
contractor grade caulk to mitigate potential water
ingestion and pressure loss.
Heater
Heater
bracket
supports
supports
9. L
ift the filter section into place at the inlet end of
heater. Secure by resting filter section onto unit’s
retaining bracket while using self tapping screws to
fasten the internal flange of the filter section the unit’s
front face.
Heater
Heater
Heater
supports
stand
stand
S-Series Technical Manual
45
Heater
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
VERTICAL INLET SKIRT
MOUNTING INSTRUCTIONS
1. Mount front panel of inlet skirt to the unit top/filter
section top/vertical stand with tek screws as needed.
4. Secure the front panel to the side panels with tek
screws through the clearance holes provided in the
panels.
2. Mount side panels to the unit/filter section/vertical
stand with tek screws as needed.
5. Secure the close-off panel to the side panels with tek
screws through the clearance holes provided in the
panels.
3. Mount close-off panel to the unit/filter section/vertical
stand with tek screws as needed.
6. Caulk all seams (8 seams typ.)
VERTICAL UNIT
CLOSE-OFF PANEL
SIDE PANEL
3
5
1
2
FRONT PANEL
4
SIDE PANEL
Cambridge Air Solutions
46
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
RAIN HOOD INLET SKIRT
1.Assemble the lower skirt section with the sheet
metal screws provided.
5.Clamp the skirt extensions on the inside of the
inlet skirt (as shown) so that the skirt extension
is flush to the exterior wall. Secure the extension
to the rain hood with the sheet metal screws
provided. Secure the extension to the building
exterior with hardware provided by others.
(Typical both sides.)
2.Assemble the upper skirt section with the sheet
metal screws provided.
3.Attach the upper skirt assembly to the lower skirt
assembly with the sheet metal screws provided.
4.Hang the upper skirt portion from the rear lip of
the rain hood and rotate forward into place. Secure
with the sheet metal screws provided.
S-Series Technical Manual
6. Caulk all seams with silicone caulk.
47
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
UNIT INLET SKIRT
1.Attach the front panel of the inlet skirt to the unit
top with the sheet metal screws provided.
4.Clamp skirt on the inside of the side panel (as
shown) so that the skirt extension is flush to the
exterior wall. Secure the extension to the side
panel with the sheet metal screws provided.
Secure the extension to the building exterior with
hardware provided by others. (Typical both sides.)
2.Attach the side panels to the unit sides with the
sheet metal screws provided. (Typical both sides.)
3.Secure the front panel to the side panels with the
sheet metal screws provided through the clearance
holes in the front panel.
Cambridge Air Solutions
5. Caulk all seams with silicone caulk.
48
S-Series Technical Manual
INSTALLATION INSTRUCTIONS
GAS PIPING
mCAUTION:
An adequate sediment trap must be installed upstream
of all gas controls for the heater and as close to the gas
inlet connection of the heater as practical.
IMPORTANT
Refer to the heater name plate for determining the
minimum gas supply pressure for obtaining the maximum
gas capacity for which this heater is specified. Any fieldinstalled components including, but not limited to, meters,
regulators, strainers and external gas trains must be
installed such that the minimum operating supply pressure
for obtaining the maximum gas capacity is provided.
IMPORTANT
Units with external gas trains must be installed so that the
equivalent distance from the outlet of the gas train to the
inlet of the heater does not exceed 4 feet.
.1.Check with the local utility or gas supplier to determine
the gas supply pressure.
CAUTION:
If the gas supply pressure is in excess of the
maximum standing pressure indicated (14” WC, or 1
PSIG, or 2 PSIG, or 5 PSIG) on the heater nameplate,
a separate positive shutoff high pressure regulator must
be added upstream of the heater’s individual manual
shutoff valve. This regulator must be vented to the
outside of the building at least 10 feet from any intake
opening. The vent pipe should be designed to prevent
the entry of water, snow, insects or other foreign
material that could cause blockage. There must be no
reduction in size of the vent piping. Depending on the
length and the configuration of the vent piping the pipe
size may need to be increased. Refer to the applicable
codes for proper sizing.
IMPORTANT
Many gas train components are equipped with Listed
Vent Limiters as atmospheric bleeds, however, local codes
may require that these vents and bleeds be vented to the
outdoors. If so, the vent piping should be designed to
prevent the entry of water, snow, insects or other foreign
materials that could cause blockage.
6.Apply test pressure to the supply piping system and
check for leaks. Use liquid gas detector.
2.Properly size the gas supply piping for the rated input
capacity, per local codes, and/or the National Fuel Gas
Code, NFPA 54/ANSI 223.1 or the CAN/CSA B149
Installation Codes.
mWARNING:
Do not use flame for leak checking.
3.Make sure the supply piping is free of foreign matter and
purged.
mCAUTION:
If the test pressure is in excess of 1/2 PSIG
(3.45 KPA), the heater and its manual shutoff valve
must be disconnected from the gas supply system
during pressure testing. Failure to comply will void
warranty.
4.Verify that the gas piping, when installed, will not restrict or
block the unit access door from fully opening.
5.Install the gas piping to the unit in accordance with
local codes or, in their absence, in accordance with the
National Fuel Gas Code, NFPA 54, NFPA 54/ANSI
223.1 or the CAN/CSA B149 Installation Codes.
I f the test pressure is less than or equal to 1/2 PSIG (3.5
KPA), the heater must be isolated from the gas supply piping
by closing its manual shutoff valve during pressure testing.
IMPORTANT
A 1/8” NPT tap is supplied with the heater for measuring
the gas supply pressure. If the gas supply pressure exceeds
that indicated on the nameplate, the installer must install
a 1/8” NPT tap and high pressure manual shutoff valve
upstream of the high gas pressure regulator.
S-Series Technical Manual
mWARNING:
Do not attempt to start unit at this time. Premature startup can result in damage to equipment and components.
49
Cambridge Air Solutions
INSTALLATION INSTRUCTIONS
ELECTRICAL WIRING
mCAUTION:
Observe special notes and instructions on Wiring
and Connection Diagrams regarding sensor
installation:
IMPORTANT
Before attempting electrical installation, review the
following instructions and the wiring and connection
diagrams to make sure you have a thorough
understanding of the requirements.
The wiring for any temperature sensors or set point
controls mounted remotely from the remote control
station must be shielded, twisted-pair wiring and must
be run separately from other AC line voltage wiring.
This also applies to other remotely mounted controls
utilized in the EDSM and EDR control systems.
mWARNING:
High voltage electrical input to this equipment is
required. Extreme caution should be exercised.
This equipment must be electrically grounded in
accordance with local codes or in accordance with
National Electrical Code ANSI/NFPA No. 70 or
the Canadian Electrical Code C22.1.
If the thermistor is not mounted remotely from the
remote control station, trim the excess wire length
from the thermistor, as required.
Shielded wire which is routed to the heater’s electrical
control enclosure should extend beyond the high
voltage section of the enclosure before the shielding
is removed and the wiring is distributed to its ultimate
destination.
1. Check the heater nameplate to determine the
voltage and amperage requirements.
IMPORTANT
Do not proceed with installation unless the supply
voltage agrees with the nameplate voltage. If supply
voltage does not agree with nameplate voltage,
check with your local agent or Cambridge Air
Solutions' Customer Service Group at 1-800-4734569 to determine what changes are required.
Shielding must be grounded at the remote control
station end only.
5. Wire the remote control station and other
temperature control options using Class 2 wiring
per the Cambridge wiring diagram and National
Electrical Code Article 725 or Canadian Electrical
Code C22.1 section 16 or local codes.
2. Install the supply wiring and adequate Branch
Circuit Protection in accordance with National
Electric Code ANSI/NFPA 70 or Canadian
Electrical Code C22.1.
6.Connect the supply wiring to the disconnect switch
inside of the heater’s electrical enclosure per
National Electrical Code, Article 430, ANSI/NFPA
70 or Canadian Electrical Code C22.1 Sections 12
and 28.
3. Mount the remote control station. This panel should
be located inside of the building and convenient to
the operator without being susceptible to damage.
4. Any temperature sensors should be located along
a perimeter wall and out of the direct path of the
discharge air or air infiltration. Consult the design
drawing and/or Cambridge’s Customer Service
Group for placement assistance. Do not locate
remote mounted temperature sensors immediately
adjacent to overhead doors because infiltration air
can affect the sensor when the door is closed and
the sensor may not adequately sense the temperature
when the door is open. In this application, the sensor
should be located on the first column in from the
outside wall when feasible.
Cambridge Air Solutions
IMPORTANT
Power and control wiring inlets on all outdoor units
must be sealed with silicone caulk (see page 56).
eturn the wiring diagram to the manual holder.
7. R
Replace and fasten all access covers.
mWARNING:
Do not attempt to start unit at this time.
Premature start-up can result in damage to
equipment and components.
50
S-Series Technical Manual
REMOTE CONTROL STATION AND
TEMPERATURE SENSOR LOCATIONS
The standard remote control station offerings for S-Series
heaters are the Remote Control Station – Security (RCS-S)
and the Temperature Setback System (TSS). For the purpose
of this discussion, both the RCS-S & TSS will be considered
to be remote control stations. An electronic thermostat is
included in the RCS. Remote control stations (RCS) and temperature sensor(s) should be mounted inside the building, not
exposed to the weather. Choosing the locations for the RCS
and the temperature sensor(s) may depend on several factors:
•C
onsiderations for temperature sensor
location include:
•W
hat is the nature of the area to be
heated by this heater?
o Is it in a warehouse?
o Is it a shipping/ receiving area?
o Is it in a manufacturing plant?
o How large is the area to be heated?
o Where are the major sources of cold air infiltration?
o How sensitive is the area to temperature changes?
o Locating the sensor so it is not in the heater discharge, which can cause the heater to short cycle.
o Locating the sensor near any heat sources such as
ovens, transformers, infrared heaters, etc. could
cause it to short cycle or not turn on.
o Locating the sensor so that it can readily respond
to changing temperature conditions, such as opening a dock door or overhead door.
o Locating the sensor immediately adjacent to a
dock door, an overhead door or a wall opening
could subject the sensor to a cold airstream, causing the heater to run more than necessary, increasing the gas bill unnecessarily.
o “Burying” the temperature sensor in a location
surrounded by product so that the sensor is unable
to readily respond to changing conditions.
o Mounting the sensor at a height above the floor,
typically about 5’ AFF, so that it is sensing the
temperature being felt by the employees in the
area.
o For freeze protection jobs, mounting the sensor at
roof joist level, so that it is sensing the temperature being felt by the sprinkler piping (wet system).
•W
hat is available regarding mounting
surfaces for the RCS and sensors?
o Exterior wall
o Columns located along the exterior wall
o Interior columns located one or two bays into the
building from the dock doors
• For a unit with TAS-2 (Temperature Averaging System)
•C
onsiderations for RCS location
include:
o Accessibility by service technicians without the
need for a man lift
o Protection from damage from cranes, fork trucks,
material handling, etc.
o Accessibility by plant employees who may be
interested in changing the thermostat settings without permission
o The RCS may be located in an equipment/operations room with the temperature sensors run to the
conditioned space.
S-Series Technical Manual
o TAS-2 can be used in conjunction with the RCS to
average the space temperature between two distant
points within a facility.
o The TAS-2 assembly comes with a total of four
thermistors, two sets of two thermistors, which are
wired in series. Once installed, each set is wired
back to the thermostat in parallel.
51
• The result is a series/parallel combination
intended to simulate a single thermistor
response.
o In a dock area, it often is beneficial to install the
sensors on columns to the right and left of the
RCS (also mounted on a column), perhaps 1 – 2
columns away from the RCS.
Cambridge Air Solutions
•W
iring
o Wiring from the heater to the RCS is 24 VAC
Class 2 control wiring, 7 to 10 wires (typical), 18
AWG minimum.
• It should be run separately from the
power wiring.
• Consideration should be given to the
appropriate wire gauge needed for the
length of wire required.
o For remote temperature sensors, use 2-wire shielded twisted-pair, 18 AWG minimum.
• The 2-wire shielded twisted-pair is low
voltage DC control wiring. It can be run
in the same conduit with other low voltage DC control wiring.
• It should be run separately from the AC
power wiring.
• Consideration should be given to the
appropriate wire gauge needed for the
length of wire required.
• The shield should be grounded at the RCS
end only.
Cambridge Air Solutions
52
o For Electronic Discharge – Space Modulation
(EDSM) and Electronic Discharge – Remote
(EDR)
• Run 2-wire shielded twisted-pair, 18
AWG minimum, from the heater to terminals 21 & 22 the RCS.
• The 2-wire shielded twisted-pair is low
voltage DC control wiring. It can be run
in the same conduit with other low voltage DC control wiring.
• It should be run separately from the AC
power wiring.
• Consideration should be given to the
appropriate wire gauge needed for the
length of wire required.
• The shield should be grounded at the RCS
end only.
S-Series Technical Manual
THERMISTOR SENSOR
The thermistor enclosure is packed inside the Remote Control
Station for shipment. It can be mounted on the exterior sides
or bottom of the Remote Control Station (see Figure 1). It
can also be mounted in a remote loca-tion within 500 feet of
the Remote Control Station using 18 gauge stranded, twistedpair, shielded cable. The thermistor is wired to the TEMP.
SENSOR terminal block on the thermostat.
THERMISTOR INSTALLATION
(See Figure 2)
1. Insert the star bushing through the opening in
the enclosure.
2. Run the thermistor leads through the star bushing.
3. Attach the cover to the enclosure over the thermistor sensor.
4. Separate and strip the ends of the lead wires
3/8".
5. Open the terminal blocks for the sensor connections.
6. Insert the lead wires and close the terminal
blocks to the locked position.
Figure 1
TEMPERATURE AVERAGING (TAS-2) OPTION
(See Figure 3)
NOTE: For remote sensors connected with shielded
cable, ground the shield at the thermostat end only.
S-Series Technical Manual
The TAS-2 option allows one thermostat to have two
sensing locations. Each enclosure has two thermistor
sensors prewired in series (see A). The sensor leads
are then connected to the thermostat in parallel (see B).
The thermostat display will show the average of the
tempera-tures at the two sensing locations. The TAS-2
is a unique application. Consult the design drawing and/
or your Cambridge Representative for placement assistance.
53
Cambridge Air Solutions
START-UP INSTRUCTIONS
1. VISUAL INSPECTION OF EQUIPMENT
a. Check for any physical damage from shipping or
installation that could render the heater inoperable.
START-UP PROCEDURE
1. Visual Inspection Of Equipment
b. Verify that all heater accessories and filters (if
applicable) have been properly installed.
2. Electrical Supply Voltage Verification
c. Check for loose components (belts, plugs, screws,
blower wheel lugs, etc.).
(page 54)
(page 54)
d. On units with external gas trains, verify that the
distance from the last safety shut-off valve to the
heater does not exceed four feet.
3. Gas Supply Pressure Verification
(page 54)
4. Blower Rotation Check
e. Verify that the field wiring, both primary and
control, has been installed according to the
Cambridge wiring diagram, National Electrical
Code, and local electrical codes.
(page 55)
5. Motor Amp Draw Check
(page 55)
f. V
erify that a sediment trap has been installed
upstream of all gas controls.
g. Verify that the high pressure regulator, if
applicable, has been vented to the outside at least
10' from the heater intake.
6. Burner Manifold Pressure Adjustment
(page 55)
7. Minimum Fire Adjustment
(page 56)
8. Calibration Check
(page 57)
h. Verify that the unions in the gas piping located at
the burner and just external to the heater housing,
are tight.
9. Gas Train Leak Check
(page 58)
10. Gas Valve Leak Check
2. E
LECTRICAL SUPPLY VOLTAGE
VERIFICATION
(page 58)
heck the electrical supply voltage at the disconnect
C
switch.
11. Final Heater Preparation
(page 59)
IMPORTANT
Do not proceed with start-up unless the supply
voltage agrees with the nameplate voltage. If the
supply voltage does not agree with the nameplate
voltage, check with your local agent or Cambridge
Air Solutions' Customer Service Group at 1-800-4734569 to determine what changes are required.
12. Remote Control Station Check
(page 59)
After start-up, please complete and fax the S-Series
Start Up Checklist to the Cambridge Customer
Service Group. Receipt of a completed checklist
will extend the start date for your warranty period to
the date of the start-up but not to exceed six months
from date of shipment.
3. G
AS SUPPLY PRESSURE
VERIFICATION
Check the gas supply pressure.
IMPORTANT
Read the following instructions carefully. Any
unauthorized modifications to or deviations from
these instructions will void the warranty.
Cambridge Air Solutions
IMPORTANT
Do not proceed with start-up unless the gas
supply pressure agrees with nameplate pressure
requirements. If the gas supply pressure is in excess
of the maximum pressure indicated, a separate
54
S-Series Technical Manual
b. Check motor current at the overload on all three
legs.
positive shut-off high pressure regulator must be
added upstream of the heater’s individual low
pressure manual shut-off valve. If a high pressure
regulator is needed and has not been installed, check
with your local agent or Cambridge Air Solutions'
Customer Service Group at 1-800-473-4569 to
determine the size and capacity requirements.
c. Turn the blower service switch to the ”OFF”
position.
IMPORTANT
The average amps must not exceed 103% of the
Motor Nameplate FLA. High amperage may indicate
excessive blower RPM.
mWARNING:
When disconnect switch is activated with
enclosure open, live power is present. Only
experienced technicians with knowledge and
respect for live power should proceed beyond this
point.
6. B
URNER MANIFOLD PRESSURE
ADJUSTMENT
a. Turn the disconnect switch to the “OFF” position.
4. BLOWER ROTATION CHECK
b. Drive the modulating valve to fully open.
a. Open the access door on the electrical control
enclosure side and turn the disconnect switch to the
”ON” position.
b.1 For EDL, EDR, EDSM, and EDSM/TP control
systems, remove the wire from terminal #3 on the
amplifier (see Figure 1).
b. T
urn the blower service switch to the ”LOCAL”
position. Blower motor will start after the
motorized damper opens. Then, turn the blower
service switch to the ”OFF” position and verify
the blower is rotating clockwise from the control
enclosure side.
Figure 1
b.2.a. For EDSC control systems, remove the wires from
terminals #T1 and #T2 of the amplifier and connect
an 1100 Ω resistor across terminals #T1 and #T2 of
the amplifier
OR
Remove the discharge temperature sensor from the
discharge duct.
IMPORTANT
On a three phase system, the rotation direction of the
blower may be reversed by switching any two wires
located on the downstream side of the motor starter.
The electrical supply to the heater must be turned off
prior to switching the wiring.
IMPORTANT
Indications of loose belts include barking or
squealing when the blower starts. If these
symptoms occur, please refer to the Belt Tensioning
instructions (page 45)
b.2.b. Provide a control signal (4-20 mA / 0-10 VDC) to the
amplifier by setting the signal level thru the Building
Automation System
OR
Remove the wires from terminals #5 and #6 of
the amplifier and connect a current/voltage signal
generator to terminals #5 and #6 of the amplifier.
(Note polarity of the terminals: #5 is negative and #6
is positive)
IMPORTANT
The damper will remain in the open position as
long as the blower service switch is not returned to
the ”REMOTE” position or the Low Temperature
Cutout (LTC) function has not timed out.
b.2.c. Set the modulation level to 100% (20 mA / 10 VDC).
5. MOTOR AMP DRAW CHECK
c. Remove the 1/8" plug from the manual shut-off valve
located just prior to the burner, and connect a manometer
for the purpose of measuring the manifold pressure.
IMPORTANT
The heater access doors must be closed for this test.
d. Refer to the heater nameplate for the Manifold
Differential Pressure (MDP) and record below.
a.Turn the blower service switch to the ”LOCAL”
position and let the motor warm up.
S-Series Technical Manual
55
Cambridge Air Solutions
l. When performing a start-up proceed to the next step,
otherwise perform Final Heater Preparation (page
59).
e. Turn the disconnect switch to the “ON” position.
f. Turn the blower service switch to the “LOCAL” position.
The blower motor will start. Observe the pressure reading
on the manometer and record below. (Note whether the
reading is positive or negative.)
7. M
INIMUM FIRE ADJUSTMENT
PROCEDURE
g. U
sing the formula below, determine the required
manifold pressure reading for the manometer.
Nameplate MDP
_______ " WC
Manifold Static Pressure
(Blower Only) +
_______ " WC
Manifold Pressure Reading =
_______ " WC
The minimum fire setting is preset at the factory at
approximately 20°F rise. This minimum fire setting
is not critical in space heating applications where the
heater is cycled in response to the space temperature
sensed by an operating thermostat. In this case, the
heater should operate at the maximum discharge temperature, far from the minimum fire setpoint.
IMPORTANT
If a temperature rise of less than 15°F is desired,
a DC microammeter is required to monitor flame
signal during the adjustment procedure. Ensure
the flame current remains steady and of sufficient
strength to maintain burner operation for both consistent ignition at minimum fire and locking in the
flame safeguard relay. Do not allow the flame signal
to drop below 2.0 microamps DC.
IMPORTANT
A negative manifold static (blower only) will cause
the manifold pressure reading to be lower than the
nameplate manifold differential pressure.
IMPORTANT
The high limit may trip on warm days. If this occurs allow the high limit to cool. Turn the blower
and burner service switches to the "OFF" position.
Access high limit and manually reset. Close the unit
access doors and turn the blower and burner service
switches to the "LOCAL" position.
a. T
urn the blower service switch to the “LOCAL”
position and monitor the discharge temperature.
b. For EDL, EDR, EDSM, and EDSM/TP control
systems, remove the wire from terminal #8 on the
amplifier. This will cause the burner to light on low
fire and then fall to minimum fire.
h. T
urn the burner service switch to the “LOCAL”
position. After a delay for prepurge and igniter
warm-up, the burner will light. Allow 15 seconds
for the low fire start to time out.
c. Turn the burner service switch to the “LOCAL”
position. After a delay for prepurge and igniter
warm-up, the burner will light. Allow 15 seconds for
the low fire start to time out.
i. O
bserve the manometer reading and compare to the
manifold pressure determined above. If the manifold
pressure reading does not equal this value, adjust the
control regulator until the proper mani-fold pressure
is obtained.
d. Monitor the discharge temperature. Subtract the
temperature from step "7a" above to determine
the temperature rise. If the minimum fire does not
require adjustment, proceed to step "7h".
j. Turn the blower and burner service switches to the
“OFF” position.
k. For EDL, EDR, EDSM, and EDSM/TP control
systems, reconnect the wire to terminal #3 on the
amplifier.
e. On the MR212 modulating/regulating valve,
remove the housing cover and loosen the lock screw
(C).
For EDSC control systems, remove the 1100 Ω
resistor and reconnect the wires to terminals #T1
and #T2 of the amplifier.
OR
Replace the discharge temperature sensor in the
discharge duct.
If used, remove the signal generator and reconnect
the wires to terminals #5 and #6 of the amplifier
Cambridge Air Solutions
56
S-Series Technical Manual
b.1. On EDL control systems, the discharge temperature should match the temperature shown on the
dial located on the amplifier. The dial should be
set to 160°F.
f. R
emove the cap (A) exposing the minimum fire
adjusting screw. Turn the adjusting screw (B) to
obtain the desired minimum fire setting.
b.2. O
n EDSM and EDSM/TP control systems, the
discharge temperature should match the temperature shown on the MAX dial on the amplifier
when the Space Temperature Selector (STS) is set
to its highest setting. If the space temperature is
warm, a test resistance of 7,500 ±250 Ω should be
con-nected in the circuit in place of the STS. The
MAX dial on the amplifier should be set to 160°F.
b.3. On EDR control systems, jumper terminals
20 and 22 and turn the dial on the remote heat
adjust RHA to its highest setting to utilize the
full temperature range of the control system. On
heaters with a single temperature selection dial
on the face of the control (Maxitrol part number
TD114), set the dial to 90°F and verify that the
override temperature selector dial, which is visible
from the top of the control, is set at 40°F. The
combination of these two settings should control
the discharge tempera-ture to 130°F. On heaters
with dual temperature selection dials on the face
of the control, set the Space Heat dial to 160°F.
g. Replace the cap (A).
On the MR212 modulating/regulating valve,
tighten the lock screw (C) and replace the housing
cover.
h. Turn blower and burner service switches to the
“OFF” position.
i. Reconnect the wire to terminal #8 on the amplifier.
b.4.1. For EDSC control systems, verify the
Maximum Discharge Air Limit Range and the
Minimum Discharge Air Limit Range jumper
settings.
j. When performing a start-up proceed to the next
step, otherwise perform Final Heater Preparation
(page 59).
MAX DA LIMIT RANGE SETTINGS
8. CALIBRATION CHECK
The discharge temperature control system has been
calibrated at the factory to the specified airflow, static
pressure, and temperature rise. The actual operating
conditions may require minor adjustments to the control settings to ensure the heater functions within the
operating parameters of its listing.
a. Remove the cover of the discharge air temperature
sampling box. Refer to the Heater Configuration
(page 4) for the discharge air temperature sampling box location, and the Individual Component
Description Section (page 67) for additional information. Install a thermocouple in the grommet
inside the discharge air temperature Sampling Box,
and then reinstall the cover. Route the thermocouple
wire to a meter located outside of the unit.
S-Series Technical Manual
MIN DA LIMIT RANGE SETTINGS
57
Cambridge Air Solutions
b.4.2. P
rovide a control signal (4-20 mA / 0-10 VDC)
to the amplifier by setting the signal level thru
the Building Automation System
OR
Remove the wires from terminals #5 and #6
of the amplifier and connect a current/voltage
signal generator to terminals #5 and #6 of the
amplifier. (Note polarity of the terminals: #5 is
negative and #6 is positive).
c. Turn the burner service switch to the ”LOCAL”
position. After a delay for prepurge and igniter
warm-up, the burner will light. Allow 15 seconds
for the low fire start to time out.
d. With the burner operating, spray the complete gas
train with leak detector solution, checking all pipe
connections and plugs.
mCAUTION:
Do not allow leak detector solution to come in
contact with electrical components.
b.4.2. Set the modulation level to 100% (20 mA / 10
VDC).
IMPORTANT
The heater access doors must be closed for the remaining portion of this test.
mWARNING:
Any gas leak detected must be repaired before
unit is placed into service.
c. Turn the burner service switch to the “LOCAL”
position. After a delay for prepurge and igniter
warm-up, the burner will light. Allow 15 seconds
for the low fire start to time out.
e. Turn the blower and burner service switches to the
”OFF” position.
f. Reconnect the wire to terminal #3 on the amplifier
d. Monitor the discharge temperature until it stabilizes. Do not rush through this step.
g. When performing a start-up proceed to the next
step, otherwise perform Final Heater Preparation
(page 59).
e. The discharge temperature should be 130 ± 3°F for
heaters setup for 130°F, or 160 +0/-5°F for heaters
setup for 160°F. If the discharge temperature
complies with this requirement, no calibration is
required. If the discharge temperature does not
equal the expected value, proceed to Calibration
Procedures (page 60).
10. GAS VALVE LEAK CHECK
All heaters should be evaluated for the gas tightness
of the gas valve seat. Heaters rated over 400,000
Btu/hr are equipped with a leak test facility to assist
in checking this seal. A momentary switch and a
gas port for measuring pressure between the valves
are provided for leak testing. Refer to the Individual
Component Description Section for more information
regarding the leak test switch (page 106).
f. Remove any jumpers that were installed previously.
g. When performing a start-up proceed to the next
step, otherwise perform Final Heater Preparation
(page 59).
a. Connect a 0-10” WC manometer to the 1/8” NPT
fitting on the manual shut-off valve located just
prior to the burner and verify the manometer is
properly zeroed.
9. GAS TRAIN LEAK CHECK
a. On EDL, EDR, EDSM, and EDSM/TP control
systems, remove the wire from terminal #3 on the
amplifier. This will drive the modulating valve to
full open.
b. On single redundant valve applications (heaters
rated less than or equal to 400,000 Btu/hr), close
the manual burner shut-off valve and wait 30
seconds to read the manometer. If the reading
is greater than 0” WC, replace the gas valve
and retest. If the reading is 0” WC, remove the
manometer and reinstall the pipe plug.
b. Turn the blower service switch to the ”LOCAL”
position. Blower motor will start after the
motorized discharge damper opens.
Cambridge Air Solutions
58
S-Series Technical Manual
On separate redundant valve applications, close
the manual burner shut-off valve, hold the momentary
leak test switch in the closed position and wait 30
seconds to read the manometer. If the reading
is greater than 0” WC, refer to the Maintenance
Instruction Section for information on Gas Valve
Cleaning for the safety shut-off gas valve closest
(SSV) to the burner and retest. If the reading is 0”
WC, remove the manometer and reinstall the pipe
plug.
b. Ensure the discharge temperature settings comply
with the application specifications.
c. If inlet ducting is utilized, determine the time
required to purge it with four (4) air changes and
select a prepurge time that will accommodate this
time. Refer to Individual Component Description
for additional information on the multi-functional
PC board.
d. Perform a visual inspection of all wiring and gas
valve plugs to ensure they have been properly
replaced.
To check the gas tightness of the SOV shut-off
valve in the gas train, connect the manometer to
the leak test port between the valves and wait
30 seconds to read the manometer. If the reading
is greater than 0” WC, refer to the Maintenance
Instruction Section for information on Gas Valve
Cleaning for the shut-off gas valve farthest from the
burner (SOV) and retest. If the reading is 0” WC,
remove the manometer and reinstall the pipe plug.
e. Return the Technical Manual and the Wiring
Diagram to the manual holder.
f. T
urn the blower and burner service switches to the
“REMOTE” position.
IMPORTANT
Turn the disconnect handle to the “OFF” position
before closing the control enclosure door.
11. FINAL HEATER PREPARATION
a. On EDSM and EDSM/TP control systems, if
the remote control station hasn’t been tested and
the ambient temperature is at or above the Entering
Air Thermostat (EAT) set point, note the set point
position and pull the jumper off the temperature set
point (EAT Enabled Mode) and reinstall it sideways
on the terminal block (Bypass Mode) as shown
in Figure 1. Refer to the Individual Component
Description section for additional information.
g. Replace and fasten all covers and panels. Close the
control enclosure and latch the door.
h. T
urn the disconnect switch to the “ON” position.
12. REMOTE CONTROL STATION CHECK
a. For EDSM and EDSM/TP control systems, if
the ambient temperature is at or above the Entering
Air Thermostat (EAT) setpoint, note the setpoint
position. Pull the jumper off the tem-perature
setpoint (Normal Mode) and reinstall it sideways
on the terminal block (Bypass Mode) as shown
in Figure 1. Refer to the Individual Component
Description section for additional information.
Figure 1
mWARNING:
All safety controls must be returned to normal operating conditions.
Figure 1
S-Series Technical Manual
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Cambridge Air Solutions
b. Insert key and turn the mode selector switch to the
“HEATING” position.
CALIBRATION PROCEDURES
EDL CONTROL SYSTEMS
(MAXITROL SERIES 14)
c. Set the operating thermostat, if applicable, to its
highest setting or activate that part of the control
system which will initiate blower and burner
operation
1. Turn the blower and burner service switches to the
“OFF” position.
2. Turn the heater disconnect switch to the “ON”
position.
For Remote Control Station - Security (RCS-S),
refer to the Operating Instructions for the Operating
Electronic Thermostat (OET) (page 64).
3. Adjust the temperature setting on the amplifier dial
to 160°.
For Temperature Setback System (TSS), refer to the
Operating and Programming Instructions for the
TSS Controller (page 66).
4. Turn the blower service switch to the “LOCAL”
position. The blower motor will start.
If another interlock device controls the operation of
the heater, activate this device.
5. Turn the burner service switch to the “LOCAL”
position. After a delay for prepurge and igniter
warm-up, the burner will light. Allow 5 minutes for
the sampling box temperature to stabilize.
d. After the motorized discharge damper opens, the
blower motor will start.
6. Adjust the calibration potentiometer as shown in
the drawing. To raise the discharge temperature
adjust the dial clockwise. To lower the discharge
temperature adjust the dial counterclockwise.
e. After a delay for prepurge and igniter warmup, the
burner will ignite.
f. Adjust the temperature control system and verify the
heater output changes correspondingly.
For EDSM, adjust the Space Temperature Selector.
For EDR, adjust the Remote Heat Adjust.
g. Reset the operating thermostat, if applicable, and
the temperature control system, if applicable, to the
desired temperature. If the Entering Air Thermostat
was adjusted, reset to its previous setting.
7. Wait for the discharge temperature and manifold
pressure to stabilize. Do not rush this step.
8. Repeat steps 6 and 7 until the mixing box
temperature has stabilized at 155°-160°.
h. Turn the mode selector switch to the “SUMMER
VENTILATION” position. Verify the blower operates. In TSS applications, the override timer may
need to be activated to initiate operation.
9. Remove the thermocouple from the Sampling Box
port and replace the Sampling Box cover. Close the
heater access doors.
i. Turn the mode selector switch to the desired
operating mode.
10. Verify that the discharge temperature and
manifold pressure comply with the guidelines of
the Calibration Check procedure step 8b. Repeat
steps 1 through 9 if necessary.
11. Turn the disconnect switch to the “OFF” position.
12. Turn the blower and burner service switches to the
“REMOTE” position.
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S-Series Technical Manual
e. Carefully remove the DTS from the sampling
box, turn it over and adjust the DTS calibration
potentiometer shown in the drawing. To raise the
discharge temperature, adjust the potentiometer
90˚ counterclockwise.
13. Close the electrical enclosure door and tighten the
latches.
14. T
urn the disconnect switch to the “ON” position.
EDSM AND EDSM/TP
CONTROL SYSTEMS
(MAXITROL SERIES 44)
1. Remove the two mounting screws from the
Maxitrol A1044 Amplifier located in the Electrical
Control Enclosure. Refer to the Electrical Control
Enclosure Isometric Drawing (page 91) for
additional information.
f. C
arefully reinstall the DTS. Replace the
Discharge Air Temperature Sampling Box cover,
and close the unit access doors.
2.Turn the amplifier over and adjust the amplifier
calibration potentiometer shown in the drawing.
To raise the discharge temperature, use a Phillips
screwdriver to adjust the potentiometer counterclockwise. To lower the discharge temperature,
adjust the potentiometer clockwise.
g. Turn the blower and burner service switches to
the ”LOCAL” position. After a delay for the
prepurge and igniter warm-up, the burner will
light.
h. Wait for the discharge temperature to stabilize.
Do not rush this step.
i. Repeat steps 4a through 4h until the manifold
pressure and discharge temperature comply with
the guidelines of the Calibration Check procedure
step ”8b” (page 57).
3. Wait for the discharge temperature and manifold
pressure to stabilize after making adjustments. Do
not rush this step.
5. Reinstall the amplifier that was removed in
step 1 (page 61).
4. In rare cases, the amplifier calibration potentiometer
will reach its adjustment limit before the proper
discharge temperature is achieved. If this occurs,
the Discharge Temperature Sensor (DTS) will need
to be adjusted:
a. Turn the burner service switch to the ”OFF”
position and allow the Discharge Air
Temperature Sampling Box time to cool.
EDR CONTROL SYSTEMS
(MAXITROL SERIES 14)
1. Turn the burner and blower service switches to the
”OFF” position.
2. Label and then remove the wires from terminals 1
through 3 of the Remote Heat Adjustment (RHA)
in the remote control station.
b. T
urn the blower service switch to the ”OFF”
position.
c. Open the unit access door on the control
enclosure side.
3. Remove the RHA from the remote control station.
Take the RHA to the unit control enclosure. See
Individual Component Description (page 106) for
RHA details, and Heater Configuration (page 5) for
electrical control enclosure location.
d. R
emove the access cover from the Discharge
Air Temperature Sampling Box and remove the
two mounting screws from the DTS. Refer to
the Individual Component Description Section
(pages 103–109) for additional information.
S-Series Technical Manual
4. Remove the wires from terminals 21 and 22 of the
right-hand side of Terminal Block #1 in the unit
control enclosure. Connect these wires to terminals
1 and 3 of the RHA.
61
Cambridge Air Solutions
5. Place a jumper between terminals 2 and 3 of the
RHA.
6. For the single dial RHA, the jumper activates the 0
to 40°F override dial. Verify the override temperature
selector dial is set to 40°. Verify the dial on the face
of the RHA is set to 90° to obtain a setpoint of 130°.
For the dual dial RHA, the jumper activates the
Space Heat selector dial. Verify the Space Heat dial
is set to 160°.
7. Turn the blower and burner service switches to the
”LOCAL” position. After a delay for the prepurge
and igniter warm-up, the burner will light.
10. Allow the discharge temperature and manifold
pressure to stabilize between adjustments until
the manifold pressure and discharge temperature
comply with the guidelines of the Calibration
Check procedure step ”8b” (page 57).
11. Turn the burner and blower service switches
to the ”OFF” position. Remove the wires
from terminals 1 and 3 of the RHA that were
connected in step 4. Reconnect the wires to
terminal 21 and 22 of Terminal Block #1 in the
unit control enclosure. Leave the jumper in place
that was applied in step 5.
12. Return the RHA to the Remote Control Station.
Reconnect the wires that were removed in
step 2.
8. Wait for the discharge temperature and manifold
pressure to stabilize. Do not rush this step. Allow 15
seconds for the low fire start to time out.
13. With the RHA reconnected in the Remote
Control Station, repeat steps 7 through 10. A
second technician and two-way communication
may be required.
9. For the single dial RHA, adjust the calibration
potentiometer shown in the drawing. To raise the
discharge temperature, adjust the potentiometer
clockwise. To lower the discharge temperature,
adjust the potentiometer counterclockwise.
14. Turn the burner and blower service switches to
the ”OFF” position. Remove the jumper from
terminals 2 and 3 of the RHA if one was added
during step 5.
or the dual dial RHA, adjust the calibration
F
potentiometer shown in the drawing. To raise the
discharge temperature, adjust the potentiometer
clockwise. To lower the discharge temperature, adjust
the potentiometer counterclockwise.
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S-Series Technical Manual
OPERATING INSTRUCTIONS
OPERATING SEQUENCE
POWER ON
1. Control transformer energized.
2. Operator must select ”SUMMER
VENTILATION” or ”HEATING” mode.
SUMMER VENTILATION MODE
1. Mode switch in ”SUMMER VENTILATION”
position.
2. Optional TSS Controller schedule calls for
ventilation.
3. Optional motorized damper opens.
4. Blower motor starts.
5. Unit continues to run until turned off.
HEATING MODE
1. Mode switch in ”HEATING” position.
2. Thermostat or interlock calls for heat.
3. Optional motorized damper opens.
4. Blower motor starts.
5. Airflow switch closes.
6. Entering air thermostat closes when inlet
temperature is below setpoint after the prepurge
delay.
7. Igniter warm up timing.
8. Gas valve opens.
9. Burner lights.
10. Igniter is de-energized.
11. Low Fire Start is de-energized after 15 seconds.
12. Unit runs and modulates until operating
thermostat and/or interlock opens (heater shuts
off).
13. Steps (2) through (12) repeat themselves
automatically as necessary.
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Cambridge Air Solutions
OPERATING INSTRUCTIONS
ELECTRONIC THERMOSTAT
The Cambridge Air Solutions Operating Electronic Thermostat (OET) controls the heater’s ON/OFF
operation in a space heating mode. It includes the following features:
• Digital LED display of current temperature and temperature settings.
• LED indication of status of output relay.
• Separate settings for HEAT ON and HEAT OFF settings.
• Temperature Calibration for accurate temperature control.
• EEPROM storage maintains temperature settings indefinitely in case of power loss.
The thermistor enclosure (SH-1) is packed inside the Remote Control Station for shipment. It can be
mounted on the exterior sides or bottom of the Remote Control Station or a remote location within
500 feet of the Remote Control Station using 18 gauge stranded, twisted-pair, shielded cable. The
thermistor is hard wired to the temperature sensor terminal block.
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S-Series Technical Manual
SETTING TEMPERATURES
TEMPERATURE CALIBRATION
The Operating Electronic Thermostat requires two
temperature settings. When the temperature drops below
the HEAT ON setting, the heater will turn on. When
the heater raises the space temperature above the HEAT
OFF setting, the heater will turn off. This difference
provides an adjustable range of operation for the heater
which minimizes temperature swings.
To compensate for lead wire resistance, it may be
necessary to make an adjustment to the displayed
temperature to correct it to the temperature measured at
the thermistor sensor. The calibration feature allows the
displayed temperature to be offset either above or below
the actual sensed temperature. Be sure to use an accurate
temperature meter for making this correction.
The minimum run time and off time for the heater
regardless of temperature are both set at 2 minutes. The
allowable temperature range is 40°F to 99°F. The HEAT
OFF temperature can not be set lower than the HEAT
ON temperature.
1. Press and hold the HEAT ON and HEAT OFF buttons
while pressing the UP or the DOWN button until the
correct temperature is displayed. ( A period [.] after
the temperature will indicate the Calibration Mode).
1. P
ress and hold the HEAT ON button while pressing
the UP or the DOWN button until the desired
temperature for the heater to turn ON is displayed.
2. Pressing the UP or the DOWN button will display the
current calibration difference above or below (-) the
measured temperature.
2. Press and hold the HEAT OFF button while pressing
the UP or the DOWN button until the desired
temperature for the heater to turn OFF is displayed.
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Cambridge Air Solutions
OPERATING INSTRUCTIONS
TSS CONTROLLER
The Cambridge Air Solutions TSS Controller provides several features to tailor the operation of the Cambridge
heating system to particular applications.
• Seven day programmable clock.
• Separate temperature settings for Heating and Setback operation.
• Separate schedules for Summer Ventilation and Heating modes.
• Setback Override for temporary heating operation.
• Real-Time Clock with automatic adjustment for Daylight Saving Time.
• Nine Holiday Setback Periods for temporary setback operation.
• Temperature Calibration for accurate temperature control.
• Capacitor backup maintains current time and day of week for power loss of up to 96 hours.
• EEPROM storage maintains schedules and temperature settings indefinitely.
The thermistor enclosure (SH-1) is packed inside the Remote Control Station for shipment. It can be mounted
on the exterior sides or bottom of the Remote Control Station or a remote location within 500 feet of the Remote
Control Station using 18 gauge stranded, twisted-pair, shielded cable. The thermistor is hard wired to the
temperature sensor terminal block.
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S-Series Technical Manual
SETTING CURRENT DAY OF WEEK, TIME,
MONTH/DAY, AND YEAR
For proper operation of the scheduler, the TSS Controller
clock must be set to the correct day of week, time,
month/day and year. In the event of power loss of more
than 96 hours, these settings must be updated.
3. Press and hold the MONTH/DAY button while pressing
the UP or the DOWN button until the current date is
displayed.
During normal operation, the TSS Controller display will
alternate between the current space temperature and the
current time and day of the week.
1. P
ress and hold the DAY OF WEEK button while
pressing the UP or the DOWN button until the light
for the current day is illuminated.
4. Press and hold the YEAR button while pressing the
UP or the DOWN button until the current year is
displayed.
2. Press and hold the TIME button while pressing the
UP or the DOWN button until the current time is
displayed.
SETTING AUTOMATIC ADJUSTMENT FOR
DAYLIGHT SAVING TIME
The TSS Controller has the ability to automatically
detect and adjust for daylight saving time. The default
setting on the controller is to recognize daylight saving
time.
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Cambridge Air Solutions
1. Press the SETBACK SCHEDULE/EXIT button to enter
the scheduling program at the first ON cycle.
SETTING TEMPERATURES
The TSS Controller has two temperature control modes
with the keyswitch on the front of the enclosure in the
HEATING position. The HEATING mode controls
the heater when the ON time schedule is in effect. The
SETBACK mode controls the heater when the OFF time
schedule is in effect. (See SETTING SCHEDULES for
instructions on setting the ON and OFF schedules). With
the keyswitch in the SUMMER VENTILATION position
the heater fan will run based on the time schedule with
no temperature control.
HEATING MODE (ON Time Schedule)
2. Press the UP button once to enter the daylight saving
time setting (”d-SA” is displayed).
The HEATING mode requires two temperature settings.
When the temperature drops below the HEAT ON
setting the heater will turn on. When the heater raises
the space temperature above the HEAT OFF setting,
the heater will turn off. This difference provides an
adjustable range of operation for the heater, which
minimizes temperature swings. The minimum on time
and off time for the heater regardless of temperature is
2 minutes. The allowable temperature range is 41°F to
99°F.
The HEAT OFF temperature cannot be set lower than
the HEAT ON temperature.
3. Press and hold the YEAR button while pressing the
UP or the DOWN button to scroll to ”YES” if daylight
saving time should be recognized or ”NO” if daylight
saving time is not recognized.
1. Press and hold the HEAT ON button while pressing
the UP or the DOWN button until the desired
temperature for the heater to turn ON is displayed.
4. Press the SETBACK SCHEDULE/EXIT button to exit
the scheduling program.
Cambridge Air Solutions
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S-Series Technical Manual
the HEAT ON and HEAT OFF temperature settings for
the amount of time set on the OVERRIDE timer.
2. Press and bold the HEAT OFF button while pressing
the UP or the DOWN button until the desired
temperature for the heater to turn OFF is displayed.
SETTING SCHEDULES
The TSS Controller has separate programmable daily
schedules for the HEATING and the SUMMER
VENTILATION modes. The schedule currently in
effect is determined by the position of the keyswitch
in the door of the enclosure. With the keyswitch in the
HEATING or OFF position, the schedule for the Heating
Mode is accessible. With the keyswitch in the SUMMER
VENTILATION position, the schedule for the
Ventilation Mode is accessible. (This will be indicated
by the VENT MODE light on the TSS Controller being
illuminated). Before attempting to program the schedule,
determine the planned time periods for HEAT (ON)
and SETBACK (OFF) for the HEATING mode and the
planned ON and OFF time periods for the Ventilation
mode. The time that it takes to recover from the
SETBACK temperature to the HEAT temperature must
also be taken into consideration for the ON time in the
HEATING mode. The following charts can be filled in
for a reference during the programming of the schedule.
There are fifteen available ON and OFF program cycles
for both HEATING and SUMMER VENTILATION.
The first ON and OFF cycles are fixed for Monday
through Friday and should only be used when the
schedules for those days are identical. The fourteen
additional numbered cycles can be programmed for any
one day or successive days.
SETBACK MODE (OFF Time Schedule)
The SETBACK mode requires setting only the ON
temperature. The OFF temperature will be automatically
set based on the temperature difference between HEAT
ON and HEAT OFF programmed above for the HEAT
mode.
1. P
ress and hold the SETBACK TEMP. button while
pressing the UP or the DOWN button until the desired
temperature for the heater to turn ON is displayed.
NOTE: Do not program the TSS controller with
overlapping schedules, as operational errors will occur.
Whenever the heater is operating during a scheduled
ON cycle and a subsequent overlapping program is
encountered, that program will be ignored.
A Holiday Setback Schedule is available for temporary
operation in the Setback Mode of up to nine different
holiday periods without affecting the current schedules.
(See HOLIDAY SETBACK SCHEDULE section for
instructions on using this feature).
SETBACK OVERRIDE
In instances where temporary heat is desired when the
scheduler is in the SETBACK mode, the OVERRIDE
timer can be used. Setting this timer, located on the
front of the TSS panel, will override the SETBACK
temperature setting and increase the space temperature to
S-Series Technical Manual
69
All unused program cycles should not contain any
settings. Check all cycles after programming to assure
that the display for unused cycles shows ”--:--”. If
undesired settings have been entered, scroll the time
display until ”--:--” is displayed (between 11.59PM and
12.00AM for time settings; between 12.31 and 1.01 for
date settings).
Cambridge Air Solutions
HEATING SCHEDULE
Cycle
On
Time
SUMMER VENTILATION SCHEDULE
AM/PM
Off
Day
M-F
Cycle
On
M-F
Off
On 1
On 1
Off 1
Off 1
On 2
On 2
Off 2
Off 2
On 3
On 3
Off 3
Off 3
On 4
On 4
Off 4
Off 4
On 5
On 5
Off 5
Off 5
On 6
On 6
Off 6
Off 6
On 7
On 7
Off 7
Off 7
On 8
On 8
Off 8
Off 8
On 9
On 9
Off 9
Off 9
On 10
On 10
Off 10
Off 10
On 11
On 11
Off 11
Off 11
On 12
On 12
Off 12
Off 12
On 13
On 13
Off 13
Off 13
On 14
On 14
Off 14
Off 14
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70
Time
AM/PM
Day
M-F
M-F
S-Series Technical Manual
1. Switch the keyswitch on the front of the enclosure to
the desired operating mode. Allow ten seconds before
proceeding.
5. Press and bold the TIME button while pressing the UP
or the DOWN button to scroll to the desired OFF time
for Monday through Friday.
2. P
ress the SETBACK SCHEDULE/EXIT button to enter
the scheduling program at the first ON cycle.
6. If Monday through Friday is the only schedule
required, proceed to Step 14. If any additional
programming is required, proceed with the following
steps. Remember that subsequent program cycles must
not overlap with the ON and OFF times set above.
3. Press and bold the TIME button while pressing the UP
or the DOWN button to scroll to the desired ON time
for Monday through Friday.
7. Press the UP button once to step to the next ON cycle.
4. Press the UP button once to step to the first OFF
cycle.
8. Press and bold the TIME button while pressing the UP
or the DOWN button to scroll to the desired ON time.
9. Press and bold the DAY OF WEEK button while
pressing the UP or the DOWN button until the light for
the desired day is illuminated.
S-Series Technical Manual
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Cambridge Air Solutions
10. Press the UP button once to step to the next OFF
cycle.
HOLIDAY SETBACK SCHEDULE
The Holiday Setback Schedule overrides the normal
schedule and holds the space at the SETBACK
temperature. The TSS Controller allows up to nine
holiday periods (Holiday Start Date [HSD] and Holiday
End Date [HED]) to be scheduled.
HOLIDAY SETBACK SCHEDULE
Cycle
Date
HSD 1
HED 1
HSD 2
11. Press and hold. the TIME button while pressing the
UP or the DOWN button to scroll to the desired OFF
time.
12.Press and hold the DAY OF WEEK button while
pressing the UP or the DOWN button until the light
for the desired day is illuminated.
HSD 3
HED 3
HED 4
HED 4
HSD 5
HED 5
HSD 6
13. Repeat steps 7-12 until all required program cycles
have been entered.
HED 6
14. Press the SETBACK SCHEDULE/EXIT button to exit
the scheduling program.
15. V
erify that the correct current time and light for day
of the week are still displayed.
Cambridge Air Solutions
HED 2
72
HSD 7
HED 7
HSD 8
HED 8
HSD 9
HED 9
S-Series Technical Manual
1. Press the SETBACK SCHEDULE/EXIT button to enter
the scheduling program at the first ON cycle.
4. Press the UP button once to step to the first holiday
end date cycle (HEd1).
2. Press the UP button repeatedly to step to the first
holiday start date (HSd1).
5. Press and hold the MONTH/DAY button while pressing
the UP or the DOWN button to scroll to the desired
holiday end date. (NOTE: Holiday end date must be at
least one day after holiday start date).
3. Press and hold. the MONTH/DAY button while
pressing the UP or the DOWN button to scroll to the
desired holiday start date.
6. Repeat steps 2-5 until all required holiday cycles have
been entered.
7. Press the SETBACK SCHEDULE/EXIT button to exit
the scheduling program.
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Cambridge Air Solutions
TEMPERATURE CALIBRATION
To compensate for lead wire resistance, it may be
necessary to make an adjustment to the displayed
temperature to correct it to the temperature measured at
the thermistor sensor. The calibration feature allows the
displayed temperature to be offset either above or below
the actual sensed temperature. Be sure to use an accurate
temperature meter for making this correction.
1. Press and hold the HEAT ON and HEAT OFF buttons
while pressing the UP or the DOWN button until the
correct temperature is displayed. (A period [.] after the
F will indicate the Calibration Mode).
2. Pressing the UP or the DOWN button will display the
current calibration difference above or below (-) the
measured temperature.
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S-Series Technical Manual
OPERATING INSTRUCTIONS
BACNET CONTROLLER
The BACnet Controller is a native BACnet®, fully programmable, direct digital controller. It provides a
communication link between a BAS (Building Automation System) and the Cambridge heater. The controller
provides precise monitoring and control of connected points.
• BACnet® MS/TP compliant operating at up to 76.8 kilobaud
•B
TL-certified controller
tandard input points for fan status, burner status, discharge temperature, zone
•S
temperature, outdoor temperature and unit lockout status
•S
tandard output points for fan control, burner control and discharge temperature control
•S
electable operating modes (unit heater / makeup air / summer ventilation)
•R
emovable screw terminal blocks
nboard USB port for firmware upgrades
•O
•L
ocal user interface display for commissioning and monitoring
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75
Cambridge Air Solutions
NETWORK PARAMETERS
NETWORK CONNECTION
•U
se stranded 3-wire twisted pair, shielded
Before operating controllers on a bus, you must set
a valid and unique device address for each controller
on the bus through the local display or MAP gateway.
Device addresses 4 through 127 are the valid addresses
for these controllers. The MAC address is set for a
default of 4.
cable to connect to FC BUS (blue) terminals.
•R
un all low-voltage wiring and cables
separate from high-voltage wiring.
•C
onnect the – terminals in parallel with
all other – terminals and the + terminals in
parallel with all other + terminals.
•T
he FC bus Shield (SHD) terminal is
isolated and can be used to as a shield drain
connection.
_
SHD
COM
+
_
+
Daisy Chained Device
on FC Bus Segment
Terminating Device
on FC Bus Segment
SHD
COM
The baud rate is set for a default of Auto. The controller
will listen for the bus supervisor to communicate
first; then automatically set its baud rate to the bus
supervisor’s baud rate. If you anticipate critical peerto-peer communication and therefore do not want the
controllers to wait for the bus supervisor to establish the
baud rate, you can specify the baud rate for each device
immediately at startup.
FC Bus
Terminal
Block Plugs
To change any of the network settings (Device
Name, Description, Address, Device Object ID) go to
Controller > Network from the local display or MAP
gateway.
Isolated Shield
Connection
Terminal
To Next
Device on
the FC Bus
Segment
To Next
Device on
the FC Bus
Segment
NOTE: When changing any network parameters it is
recommended that the controller be disconnected from
the network while the changes are being made and that
the power be cycled to the controller after all changes
have been made before reconnecting the controller to
the network.
Stranded 3-Wire Twisted Shielded Cable
END-OF-LINE TERMINATION
If a controller is on either end of a BACnet MS/TP
network an EOL terminator (JCI # MS-BACEOL-0)
must be installed for proper network operation.
Cla
AC ss
24 2
V~
Bus
Cl
AC ass
24 2
V~
Bus
FC
WHT
BLK
REF
FC or N2 Bus
Terminals
BLU
BLK
WHT
Supply
Power
Terminals
To 24 VAC
Class 2
Power Supply
FC or Bus Cable from
Previous Device on
Daisy-Chained Bus Segment
Cambridge Air Solutions
FIG_EOLT_WRNG
EOL
Terminator
Isolate and insulate the REF
lead when connecting the
EOL to third-party devices
with only + and - terminals.
24V~Hot
WHT-
24V~
BLU
REF
BLK +
24V~Com
FC
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S-Series Technical Manual
SUMMER VENTILATION MODE
OPERATING SEQUENCES
1. If Zone Temperature (AI8) is above Zone Set
Point (AV4) then Supply Fan (BO1) starts.
2. If Zone Temperature (AI8) is below Zone Set
Point (AV4) minus Differential (AV28) then
Supply Fan (BO1) stops.
3. Supply Fan (BO1) will not operate if
Outdoor Temperature (AV20) is above Zone
Temperature (AI8).
UNIT HEATER / OCCUPIED MODE
1. If Zone Temperature is below Zone Set Point
then Supply Fan and Burner start.
2. Discharge Temperature modulates to
Discharge Set Point.
3. If Zone Temperature is above Zone Set Point
plus Differential then Supply Fan and Burner
stop.
4. Unit will not operate if Outdoor Temperature
is above Heating Lockout Set Point.
UNOCCUPIED MODE
1. If Zone Temperature is below Zone Set Point
then start Supply Fan and Burner.
2. Discharge Temperature modulates to
Discharge Set Point.
3. If Zone Temperature is above Zone Set Point
plus Differential then stop Supply Fan and
Burner.
4. Unit will not operate if Outdoor Temperature
is above Heating Lockout Set Point.
MAKEUP AIR / OCCUPIED MODE
1. Supply Fan and Burner run continuously.
2. Discharge Temperature modulates to
Discharge Set Point.
3. Burner will not operate if Outdoor
Temperature is above Heating Lockout Set
Point.
DEFAULT SETTINGS
MAKEUP AIR w/PID / OCCUPIED MODE
The controller will function to control the unit without
the network being connected, provided that a Zone
Temperature Sensor is connected.
The default settings are:
• Normal Mode = Unit Heater
• Discharge Set Point = 160°F
• Zone Set Point = 65°F
• Set Point Differential = 3°F
1. Supply Fan and Burner run continuously.
2. Discharge Temperature modulates to
Discharge Set Point based on PID loop.
3. Burner will not operate if Outdoor
Temperature is above Heating Lockout Set
Point.
MAKEUP AIR w/PID PLUS ON-OFF /
OCCUPIED MODE
1. If Zone Temperature is below Zone Set Point
plus Differential then Supply Fan and Burner
start.
2. Discharge Temperature modulates to
Discharge Set Point based on PID loop.
3. If Zone Temperature is above Zone Set Point
plus Differential then Supply Fan and Burner
stop.
4. Burner will not operate if Outdoor
Temperature is above Heating Lockout Set
Point.
S-Series Technical Manual
77
Cambridge Air Solutions
LOCAL DISPLAY
The controller includes an onboard illuminated LCD display and 4
buttons for monitoring and adjustment.
POWER
FAULT
SA BUS
FC BUS
MODBUS
Label
Name
Escape
Description
Exit the current menu level and go up one level
Enter
Access the menu
Accept the current selection
Up
Scroll through menu selections Adjust current
parameter selection
Down
TROUBLESHOOTING
POWER
FAULT
The status LEDs indicate power connection and network communication.
Label
Color
Normal State
Power
Green
On Steady
Fault
SA Bus
FC Bus
Mod Bus
Red
Green
Green
Green
Cambridge Air Solutions
SA BUS
FC BUS
MODBUS
Description
On Steady = Power Connected
Off Steady = No Supply Power. Check Output wiring for
short circuits and cycle power to the controller.
Off Steady
Off Steady = No Faults
On Steady = Device Fault: no application loaded; Main
Code download required if controller is in Boot mode,
or a firmware mismatch exists between the PEAK
controllers and the ZRF1811 Wireless Field Bus Router.
Blink - 2 Hz = Download or Startup in progress, not
ready for normal operation
Blink - 2 Hz
Blink - 2 Hz = Data Transmission (normal
communication)
Off Steady = No Data Transmission (Auto baud in
progress)
On Steady = Communication lost, waiting to join.
Blink - 2 Hz
Blink - 2 Hz = Data Transmission (normal
communication)
Off Steady = No Data Transmission (Auto baud in
progress)
On Steady = Communication lost, waiting to join.
Blink - 2 Hz
Blink - 2 Hz = Data Transmission (normal
communication)
Off Steady = No Data Transmission (Auto baud in
progress)
On Steady = Communication lost, waiting to join.
78
S-Series Technical Manual
MAINTENANCE INSTRUCTIONS
FILTERS
mWARNING:
Filters may be provided in a V-bank filter section.
Filters may be of the disposable or permanent type.
Turn the disconnect switch off when performing
service or maintenance functions.
Service the filters as needed based on the ”loading”
experienced. Clean filters typically start out with a
pressure drop across the filters between 0.15 and 0.25”
WC. Cleaning or replacement is generally required
below the pressure drop increased by a factor of 4
times the initial clean value.
BLOWER BEARING LUBRICATION
Heaters with 3 HP or smaller motors have
permanently lubricated, double shielded and double
sealed ball bearings which do not require additional
lubrication. Heaters with 5 HP or larger motors
require lubrication on intervals of 3 to 6 months. Use
Duralube AW-2G, Goldplex (Lithplex HC 150 SMG),
Shell Gadus S2V100 2 or Mobilith AW2 grease.
Grease should be bearing quality and compatible to
lithium bases thickener.
Turn off the heater before servicing the filters.
Remove the filters from the filter section by opening
the filter access door. Handle the filters carefully to
prevent debris from being dislodged from the filter
into the heater.
Permanent Filters are 2” thick expanded aluminum
washable filters in aluminum frames.
MOTOR BEARING LUBRICATION
Motors are pregreased normally with Exxon Polyrex
EM. Equivalent greases which are compatible with
the Exxon Mobil lithium complex greases and electric
motor polyurea greases per ASTM D6185.
Annual Motor
Operation
Permanent filters can be cleaned using a stream of
water or soap and water. Back flush the filters until
the water comes out clean. If soap is used, ensure that
all soap is rinsed out of the filter. Visually inspect the
filter to ensure that it is clean. Allow to dry before
returning to service.
Recommended
Lubrication Interval
NEMA 215T
Frame or
smaller
NEMA 254
Frame or
larger
Intermittent Operation >5000 hours
5 years
3 years
Continuous Operation Standard Service
2 years
1 year
Seasonal Service
(Motor is idle for 6
months or more)
Continuous Operation Severe Service
(High ambient, dirty
or moist location, high
vibration)
S-Series Technical Manual
Disposable Filters are 2” thick cotton/polyester
panels with galvanized expanded metal pleat support
grids and beverage board frames.
Disposable filters are replaced when they become
dirty. Replace the filter with the same size of filter
which is removed from the filter section. Note the
airflow markings on the filter.
1 year
6 months
79
Model
Quantity
Size
S400/S800
2
20” x 25” x 2”
S950/S1200/S1600
4
20” x 25” x 2”
S1850/S2200/S3200
12
16” x 25” x 2”
Cambridge Air Solutions
BURNER CLEANING
BELT TENSIONING
The Cambridge Air Solutions burner is for the most
part self-cleaning. However, if the application is
extremely dirty or dusty, it may become necessary to
periodically clean the burner. Remove and clean the
burner in accordance with the following recommended
procedures:
Using a Browning Belt Tension Checker and a
straight edge, verify proper belt tension according to
the following table:
Belt(s)
Center
Span
Qty Type Deflection
Force (lbs)
New
Used
Belts
Belts
Model
HP
S400/
S800
1
1
A
1/4”
2-3
1-2
S400/
S800
2
1
A
1/4”
2½ - 4
1½ - 3
S950/
S1200
2
1
BX
1/4”
3 - 4½
2 - 3½
S800/
S950/
S1200
3
2
BX
1/4”
4½ - 6
4 -5½
S1200/
S1600
5
2
BX
1/4”
3-5
2½ - 4
S1850/
S2200
5
2
BX
7/16”
5-7
4½ - 6½
S1850/
S2200
7½
2
BX
7/16”
6-8
5½ - 7
S2200/
S3200
10
2
BX
7/16”
6½ - 8½
6 - 7½
S2200/
S3200
15
2
BX
7/16”
7-9
6-8
1.Turn the heater disconnect switch off. Close the
manual gas supply shut-off valve.
2. Loosen the union in the gas train.
CAUTION:
The igniter is made of silicon carbide material
and should be handled with care to avoid
breakage.
3.Disconnect the ignition cable from the burner and
remove the flame rod and the igniter.
4.Examine the flame rod ceramic for cracks and
replace if necessary. Clean the flame rod element
with emery cloth to remove oxidation.
5.Remove the fasteners that secure the burner to the
housing. The burner will then be free to slide out.
mCAUTION:
Be sure to take necessary safety precautions (such
as wearing eye protection, etc.) before attempting
the next step.
Periodic belt adjustments may be required. Indications
of loose belts include barking or squealing when the
blower starts.
6.Clean the burner by back-flushing using high
pressure air (40-80 PSI). Continue back-flushing
until dust particles are completely expelled from
the burner.
BLOWER CLEANING
The blower wheel should be examined for
accumulation of dust on the blades. These surfaces
must be kept clean. Dirt accumulation will result
in significant air flow reduction and/or possible
imbalance of the blower wheel.
7.Reinstall the burner using the above steps in
reverse order.
mCAUTION:
GAS TRAIN LEAK CHECK
Prolonged imbalance can result in catastrophic
failure of the blower wheel and other related
components.
Cambridge Air Solutions
Periodically check the gas control assembly, internal
and external piping for leaks. Refer to the Gas Train
Leak Check procedure (page 58). All relief vents on
the gas controls should be checked for blockage (gas
pressure regulators and pressure switches).
80
S-Series Technical Manual
GAS VALVE CLEANING
IMPORTANT
If the valve has been disassembled for inspection
and cleaning only and a Rebuild Kit is not being
installed, lubricate the following with RemGrit TFL
50® Dry Lubricant:
All solenoid valves should be cleaned periodically.
The time between cleanings will vary depending on
the medium and the service conditions. In general,
if the voltage to the coil is correct, sluggish valve
operation, excessive noise, or leakage will indicate
that cleaning is required. Refer to the Gas Valve Leak
Check procedure (page 58).
• Diaphragm assembly on both sides
• Main disc at base of core/diaphragm sub-assembly
• Pilot disc at base of core assembly
mWARNING:
In the extreme case, the valve may fail to open or
fully close.
mCAUTION:
Do not distort the hanger spring between the core
assembly and the diaphragm assembly when
lubricating the pilot disc.
IMPORTANT
It is not necessary to remove the valve from the gas
train for cleaning.
5. Replace the body gasket and the core/diaphragm
subassembly with the closing spring attached.
Locate the bleed hole in the core/diaphragm subassembly approximately 30˚ counterclockwise from
the valve inlet.
mWARNING:
Before servicing the valve, turn off the electrical
power, close the upstream manual gas valve,
depressurize the valve, extinguish all open flames
and avoid any type of sparking or ignition. Vent
hazardous or combustible fumes to a safe area.
6. Replace the valve bonnet and the bonnet screws.
Torque the screws in a crisscross manner to 100
± 10 in-lbs. Replace the solenoid and make the
electrical hookup.
ASCO Gas Valves: Series 8214
Disassemble the valve (page 82) and clean all parts as
follows:
mWARNING:
Before returning to service, check the valve for
proper operation and perform Gas Valve Leak
Check and Gas Train Leak Check procedures
(page 27-28).
IMPORTANT
If parts are worn or damaged, install a complete
ASCO Rebuild Kit.
1. Remove the solenoid enclosure.
2. Remove the bonnet screws, valve bonnet, bonnet
gasket, core/diaphragm subassembly and body
gasket.
ORDERING INFORMATION FOR ASCO
REBUILD KITS
Parts marked with an asterisk (*) in the exploded
views are supplied in Rebuild Kits.
3. Lubricate the bonnet gasket and body gasket with a
light coat of Dow Corning® 200 Fluid lubricant or
an equivalent high-grade silicone fluid.
When ordering Rebuild Kits for ASCO valves,
order the Rebuild Kit number stamped on the valve
nameplate. If the number of the kit is not visible,
order by indicating the number of kits required,
and the Catalog Number and Serial Number of the
valve(s) for which they are intended.
4. Apply a light coat of RemGrit TFL 50® Dry
Lubricant to: the valve seat; the valve body surface
where the diaphragm assembly contacts the valve
body and body gasket; and the internal surface of
the valve bonnet where the diaphragm assembly
contacts the bonnet when the valve is in the
energized (open) position.
S-Series Technical Manual
81
Cambridge Air Solutions
∗
∗ Indicates parts supplied
in ASCO Rebuild Kit.
∗
BONNET SCREW
∗
BLEED HOLE
Locate bleed hole in
core/diaphragm sub--assembly approximately
30° from valve inlet
∗
CAUTION
Do not damage
valve seat
Disassembled View of ASCO Valve
Cambridge Air Solutions
82
S-Series Technical Manual
TROUBLESHOOTING INSTRUCTIONS
TROUBLESHOOTING GUIDE
Problem
I. No Blower Operation
Possible Cause
1. Unit in Reset
a) Outside temperature below LTC setpoint
in Vent Mode
b) G
as Valve not energized during call for
heat cycle
2. Heater Disconnect
a) Disconnect in OFF position
3. Mode Selector Switch on RCS
a) Switch in OFF position
b) Defective Switch
4. Operating Thermostat
a) Thermostat satisfied
b) Open in thermistor circuit
c) Defective thermostat
5. Blower Service Switch
a) Switch in OFF position
b) Defective switch
6. Control Transformer
a) No input voltage
b) Blown control fuse
c) Defective transformer
7. Class 2 Transformer
a) No output voltage
b) Defective transformer
8. Multi-Functional PC Board
a) No input voltage on Terminal G (RCS)
b) Improper wiring
c) Defective board
9. Damper Motor
a) Damper fuse tripped due to damper motor
over-stroking
b) Damper end switch not made
c) Defective damper motor
10. Motor Protection
a) Overload relay tripped
b) Overload relay defective
11. Motor Starter
a) Coil open (Defective)
b) Contacts welded closed (Defective)
12. Motor
a) No input voltage
b) Improper voltage
c) Defective motor
13. Blower
a) Defective or locked bearings
b) Physical damage
14. Belts
a) Belt Slipping
b) Belt broken or missing
S-Series Technical Manual
83
Corrective Action
a)Turn unit OFF momentarily and turn unit
ON.
b) See Problem III.
a) Turn disconnect ON.
a) Place switch in proper mode.
b) Replace switch.
a) Adjust thermostat, if applicable.
b) Check wiring or replace thermistor.
c) Replace thermostat.
a) Place switch in REMOTE position.
b) Replace switch.
a) Check disconnect and supply fusing.
b) Replace control fuse.
c) Replace transformer.
a) Check supply voltage.
b) Replace transformer.
a) Check voltage in RCS.
b)Check wiring.
c) Replace multi-functional PC board.
a) Adjust damper stroke (page 54).
b) Check end switch/cam interface.
c) Replace damper motor.
a1) Check primary power source.
a2)Reset overload relay and check motor
amps/overload setting.
b) Replace overload relay.
a) Replace starter.
b) Replace starter.
a) Check primary power source.
b) Consult factory.
c) Replace motor.
a) Replace bearings.
b) Replace or repair blower
a) Tighten belts.
b) Replace belts.
Cambridge Air Solutions
TROUBLESHOOTING INSTRUCTIONS
TROUBLESHOOTING GUIDE
Problem
II. B
LOWER RUNS;
NO HEAT;
FLAME SAFETY
RELAY DOESN’T
LOCK OUT
III. BLOWER RUNS;
NO HEAT;
FLAME SAFETY
RELAY LOCKS OUT
Possible Cause
1. Mode Selector Switch
a) Switch in VENT position
b) Defective Switch
2. Burner Service Switch
a) Switch in OFF position
b) Defective switch
3. Multi-Functional PC Board
a) No input voltage on Terminal W (RCS)
b) Inlet temperature above EAT setpoint
c) Improper wiring
d) Defective board
4. Airflow Switch
a) Blower running backwards
b) Belts slipping
c) Blocked intake or discharge
d) Clogged airflow tubing or pickup ports
e) Defective switch
5. Flame Safeguard Relay
a) No input voltage
b) Defective FSR
1. Igniter
a) No current (open igniter)
b) No voltage
2. High Limit
a) High limit tripped
3. High or Low Gas Pressure Switches
a) Low gas pressure switch tripped
b) High gas pressure switch tripped
c) Defective gas pressure switch
4. Gas Valve
a) No input voltage
b) Gas valve does not open
c) Defective solenoid
5. Modulating Valve
a) Minimum fire set too low
6. Multi-Functional PC Board
a) Low fire start set too low
b) Thermistor open or not connected
Cambridge Air Solutions
84
Corrective Action
a) Place switch in HEAT position.
b) Replace switch.
a) Place switch in REMOTE position.
b) Replace switch.
a) Check voltage in RCS.
b) Adjust EAT setpoint.
c)Check wiring.
d) Replace multi-functional PC board.
a) Reverse motor direction.
b) Tighten and/or replace belts.
c) Find and remove obstruction.
d)Clean or replace tubing or pickup ports.
e) Replace switch.
a) Check wiring.
b) Replace FSR.
During trial for ignition:
a) Check igniter current.
b) Check FSR output to igniter.
a) See Problem Number VI (page 86).
a) C
heck gas supply for low gas pressure or
no gas.
b1) Check manifold gas pressure for high
pressure reading and reset pressure
regulator.
b2) Check gas supply pressure against name
plate.
b3) Verify the high pressure regulator is a
lock-up type.
c) Replace gas pressure switch.
a1) C
heck FSR output to R1 relay
during ignition trial.
a2) Check gas valve circuit and wiring.
b1) Compare supply voltage to nameplate
voltage.
b2) Clean and/or replace gas valve parts.
c) Replace solenoid or valve assembly.
a) Adjust minimum fire on modulating valve.
a) Adjust modulating valve voltage between
10 and 13 Volts DC.
b) Properly install or replace thermistor.
S-Series Technical Manual
TROUBLESHOOTING INSTRUCTIONS
TROUBLESHOOTING GUIDE
Problem
III. BLOWER RUNS;
NO HEAT; FLAME
SAFETY RELAY
LOCKS OUT
(Continued)
IV. B
LOWER RUNS;
BURNER FIRES;
FLAME SAFETY
RELAY LOCKS OUT
Possible Cause
7. Regulator
a) Clogged vent orifice
b) No supply pressure
c) Improper manifold pressure
d) Defective regulator
8. Burner
a) Defective burner
1. Low Flame Current
a) Dirt build-up on ceramic body
b) Minimum fire set too low
c) Defective burner
2. Multi-Functional PC Board
a) Low fire start set too low
3. No Flame Current
a) Ground connection open
b) Wire termination oxidized
4. Fluctuating Flame Current
a) Unit overfiring
b) Minimum fire set too low
c) Intermittent ground connection
d) Loose terminal on Flame Rod
V. BLOWER RUNS;
UNIT HEATS;
S
HORT CYCLES
WITHOUT
RESETTING
e) Defective burner
5. Flame Safeguard Relay
a) Defective FSR
6. High Limit
a) High limit contact intermittent
1. Air Flow Switch
a) Blower running backwards
b) Belts slipping
c) Blocked intake or discharge
d) Air delivery below unit specs
e) Clogged airflow tubing or pick-up ports
f) Defective switch
2. Flame Safeguard Relay
a) Defective FSR
3. Operating Thermostat
a) Differential temperature setting too tight
b) Open or short in thermistor circuit
4. Damper Motor End Switch
a) End switch making intermittent contact
S-Series Technical Manual
85
Corrective Action
a) Clean or replace orifice.
b) Check all gas cocks and piping.
c) Adjust regulator.
d) Replace regulator.
a) Replace burner.
a) C
lean dirt deposit from ceramic body and
install protective boot.
b) Adjust minimum fire on modulating valve.
c) Replace burner.
a) Adjust modulating valve voltage between
10 and 13 Volts DC.
a1) Reference transformer to ground.
a2) S
ecure ground between control enclosure
and burner.
a3) Tighten loose ground screws.
b) Clean terminal and reinsert.
a) Check manifold pressure.
b) Adjust minimum fire on modulating valve.
c) Tighten all ground points.
d)Remove jam nuts from Flame Rod.
Reassemble with terminal located
between jam nuts on Flame Rod.
e) Replace burner.
a) Replace FSR.
a) Replace high limit.
a) Reverse motor direction.
b) Tighten and/or replace belts.
c) Find and remove obstruction.
d) Increase fan RPM for air delivery
requirements.
e) C
lean or replace airflow tubing or pick-up
ports.
f) Replace switch.
a) Replace FSR.
a) Increase differential temperature setting.
b) Check wiring or replace thermistor.
a) Replace end switch assembly.
Cambridge Air Solutions
TROUBLESHOOTING INSTRUCTIONS
TROUBLESHOOTING GUIDE
Problem
VI. H
IGH LIMIT TRIPPED
VII. B
LOWER RUNS;
UNIT HEATS;
WILL NOT CYCLE
OFF
VIII. MODULATING
VALVE DOES NOT
MODULATE;
CONTINUOUS
HIGH FIRE
Possible Cause
1. High Limit
a) High limit will not reset
2. Unit Overfiring
a) Manifold pressure too high
3. Discharge Damper
a) Damper blades partially closed
b) Defective damper motor
4. Low Airflow
a) Blower running backwards
b) Belts slipping
c) Blocked intake or discharge
5. Temperature Control System
a) Temperature control system does not
modulate
1. Operating Thermostat
a) Short in thermistor circuit
b) Thermostat located improperly
c) Thermostat differential setting too wide
d) Defective thermostat
2. Burner Service Switch
a) Switch in LOCAL position
3. Auxiliary Control
a) Auxiliary contacts closed
4. M
isunderstood Control System
Operation
a) Control system doesn’t function as
expected
1. Amplifier (A1014 or A1044 or AD1014)
a) Wire not connected to amplifier terminal
3 or 4. Also terminal 5 on A1044
amplifier
b) J umper not installed between terminals 2
and 3 of A1014 or AD1014
c) Defective amplifier
2. Discharge Temperature Sensor
(TS114J or TS144)
a) Discharge Air Temperature Sampling
Tube clogged
b) O
pen in sensor circuit
c) Sensor cross-wired to amplifier
d) Temperature Control System out of
calibration
Cambridge Air Solutions
86
Corrective Action
a) Replace high limit.
a) Adjust appliance regulator to obtain
temperature rise specified on nameplate.
a) Adjust damper stroke length.
b) Replace damper motor.
a) Reverse motor direction.
b) Tighten or replace belts.
c) Find and remove obstruction.
a) See problem VIII (page 86).
a) C
heck thermistor wiring and/or replace
thermistor.
b1) Thermostat in cold draft-relocate.
b2) Thermostat not satisfied-turn down.
c) Reduce differential setting.
d) Replace thermostat.
a) Place switch in REMOTE position.
a) C
heck auxiliary circuit wiring and
contacts.
a) R
eview control system operational
characteristics.
a) Reinstall wire.
b) Reinstall jumper.
c) Replace amplifier.
a)Clean Discharge Air Temperature
Sampling Tube (page 69).
b) R
eplace the sensor if the resistance
measured at terminals 1 and 2 on TS114J
sensor exceeds 15,000 Ω 1 and 3 or 2 and
3 on TS144 exceeds 6,000 Ω.
c) Correct wiring terminations.
d) P
erform appropriate calibration procedure
(pages 60–62).
S-Series Technical Manual
TROUBLESHOOTING INSTRUCTIONS
TROUBLESHOOTING GUIDE
Problem
VIII. MODULATING
VALVE DOES NOT
MODULATE;
CONTINUOUS
HIGH FIRE
(Continued)
Possible Cause
3. Space Temperature Selector
(Series 44 only)
a) Open in sensor circuit
b) Induced voltage in field wiring
c) Space sensor located improperly
4. Space thermostat (Series 14 only)
a) Thermostat out of calibration
b) Thermostat located improperly
c) Thermostat differential setting too wide
d) Thermostat defective
5. Remote Heat Adjust (TD114 or CEI
4175-0-960)
a) Short in Remote Heat Adjust circuit
b) Induced voltage in field wiring
6. Modulating Valve (M511, M611 or
MR212)
a) Foreign material holding valve open
b) Modulating valve misassembled
IX. M
ODULATING VALVE 1. Class 2 Transformer
DOES NOT
a) No voltage output to amplifier
MODULATE;
CONTINUOUS
LOW FIRE
2. Modulating Valve
a) Valve coil is open or shorted
b) Plunger jammed
c) Ruptured main or balancing diaphragm
3. Amplifier
a) No output voltage to valve
4. Discharge Temperature Sensor
(TS114J or TS144)
a) Short in sensor circuit
b) Temperature control system out of calibration
S-Series Technical Manual
87
Corrective Action
a) R
eplace the sensor if the resistance
measured is more than: 7,000 Ω for the
T244; 5,500 Ω for the TS244; or 2,250 Ω
for the TD244.
b) Utilize shielded, twisted pair wiring.
c) Sensor in cold draft - relocate.
a) Recalibrate thermostat or replace.
b) Thermostat in cold draft - relocate.
c) Reduce differential setting.
d) Replace thermostat.
a) R
eplace Remote Heat Adjust if resistance
measure between terminals 1 and 3 of
Remote Heat Adjust is less than 6,000 Ω.
b) U
tilize shielded, twisted pair wiring.
a) D
isassemble valve and remove foreign
material.
b) D
isassemble valve and assemble correctly.
a1) Check for short in modulating valve coil.
a2) Replace transformer.
a) R
eplace valve coil if its resistance is less
than 40 Ω or greater than 85 Ω.
b) Clean or replace plunger.
c) C
heck diaphragm condition and replace if
defective.
a) With the wire removed from terminal 3
of amplifier, replace amplifier if the valve
voltage does not exceed 18 Volts DC.
a) R
eplace the sensor if the resistance measured
at: terminals 1 and 2 on TS114J is less than
8,000 Ω; terminals 1 and 3 or 2 and 3 on
TS144 is less than 2,900 Ω.
b) P
erform temperature control system
calibration.
Cambridge Air Solutions
TROUBLESHOOTING INSTRUCTIONS
TROUBLESHOOTING GUIDE
Problem
IX. MODULATING
VALVE DOES NOT
MODULATE;
Possible Cause
5. Space Temperature Selector
(T244 or TS244/TD244)
a) Short in sensor circuit
CONTINUOUS
LOW FIRE
(Continued)
X. E
RRATIC OR
PULSATING FLAME
6. Remote Heat Adjust
(TD114 or CEI 4175-0-960)
a) Open in the Remote Heat Adjust control
circuit
7. Multi-Functional PC Board
a) Terminal X has power
b) Defective board
1. High Pressure Regulator
a) Vent undersized
b) Defective regulator
2. Amplifier
a) Hunting
b) Temperature control system out of
calibration
c) Defective amplifier
3. Space Temperature Selector
(T244 or TS244/TD244)
a) Induced voltage in field wiring
4. Remote Heat Adjust
(TD114 or CEI 4175-0-960)
a) Induced voltage in field wiring
Cambridge Air Solutions
88
Corrective Action
a) Replace the sensor if the resistance
measure is less than 5,000 Ω for the T244
or 3,500 Ω for the S244 and 1,950 Ω for
the TD244.
a) Replace the control if the resistance
measured at terminals 1 and 3 exceeds
12,000 Ω.
a) Determine power source.
b) Replace board.
a) Enlarge vent piping size or reduce vent
piping length.
b) Replace regulator.
a) Adjust sensitivity control dial counterclockwise.
b) Perform appropriate calibration procedure
(pages 60–62).
c) Replace amplifier.
a) Utilize shielded, twisted pair wiring.
a) Utilize shielded, twisted pair wiring.
S-Series Technical Manual
TROUBLESHOOTING INSTRUCTIONS
DAMPER MOTOR REPLACEMENT & ADJUSTMENT
1. Before reinstalling the damper motor into the heater
assembly, remove the black plastic weather cover
from the damper motor by removing the screw that
secures the cover to the damper assembly using
either a flat tip screw driver or a ¼” nut driver.
It may be necessary to twist the cover slightly to
disengage it from its mounting to the end of the
motor after the screw is removed.
2. V
erify the damper motor is in the CLOSED
position (Drive tube is retracted with a minimum of
1/4” gap between the drive tube and the body of the
damper assembly).
Figure 1
5. Verify the heater disconnect switch is turned OFF
and the service switches are in the OFF position.
3. Verify
the inner cam has fully engaged the lower
limit switch plunger and the lower limit switch
(next to the body of the damper motor) shows
continuity between the common (C) terminal and
the normally open (NO) terminal.
6. Connect the wires to the terminals as shown in
Figure 2 and reinstall the cover.
mCAUTION:
If the lower limit switch does not indicate
continuity, the damper motor must be driven to
the fully CLOSED position BEFORE connecting
the damper linkage tube to drive tube of damper
motor assembly.
IMPORTANT
If the drive tube bottoms out against the damper
motor housing, damage to the PC board or tripping
of the onboard fuse may result. If the fuse trips, place
the blower service switch in the OFF position for 15
seconds to allow fuse to reset. Proceed with steps 4
through 10 PRIOR to connecting the damper motor to
the linkage tube.
Figure 2
7. Remove the push-in plug (located in the weather
cover) to have access to the upper cam adjusting
nut.
8. Connect the motor pivot to the damper motor
support bracket using the 3/8” diameter clevis pin.
4. Verify the cam location on the upper cam is set just
short of the four o’clock position with respect to the
switch plunger being the twelve o’clock reference
position. If it is beyond the four o’clock position,
use a deep well 1/2” hex socket or nut driver and
manually rotate the cam counterclockwise a few
clicks, as required, to obtain the correct starting
position. (Refer to Figure 1.)
S-Series Technical Manual
IMPORTANT
Do not connect the damper linkage tube at this time.
9. Remove the wire from the ”G” terminal of the
terminal block. (This is to avoid a ”Call-for-Fan”
signal from the remote control station during the
next two steps).
89
Cambridge Air Solutions
10. Suspend the damper motor assembly from
the damper motor support bracket. Turn the
disconnect switch on and turn the blower
service switch to the ”LOCAL” position for
approximately 5 seconds.
IMPORTANT
Damper blades should be snug to avoid fluttering in
the high velocity air stream.
IMPORTANT
Do not restrain the drive tube from turning freely.
11. Turn the blower service switch to the ”REMOTE”
position until the damper motor drive tube stops
turning. (Drive tube is now fully retracted).
12. Turn the disconnect switch off. Manually trip the
motor starter overload using the manual trip lever
located on the overload between the overload and
the motor starter.
Figure 3
mCAUTION:
Do not over-drive the damper motor as damage to
the PC board or tripping of the onboard fuse may
result. If the fuse trips, place the blower service
switch in the ”OFF” position for 15 seconds to
allow fuse to reset.
13. Slide the damper linkage tube into the drive tube
and align the hole in the drive tube with the hole
in the damper linkage tube by manually rotating
the drive tube in 1/2 turn increments until the
5/16” diameter clevis pin can pass through both
parts. Lubrication of the damper linkage tube
may be required. Maintain the damper blades in
the tightly-held, fully closed position during this
adjustment.
17. Turn the blower service switch to the ”REMOTE”
position and, after the damper motor closes, turn
the disconnect switch off.
14. Turn the disconnect switch on and turn the blower
service switch to the ”LOCAL” position. The
damper will open to the point the upper cam
engages the upper limit switch.
18. Reinstall the plastic plug from the damper
viewport and the weather cover push-in plug.
19. Reconnect the wire removed in step 9 to terminal
”G”.
15. Remove the plastic plug from the damper viewport
(located on the exterior side of the heater housing
toward the discharge end). It may be helpful
to place a flashlight inside the heater housing
to observe the damper linkage tube travel to
ultimately rest against the hex shaft.
20. Reset the motor starter overload.
21. Verify that both service switches are in the
”REMOTE” position, close the electrical
enclosure door and turn the disconnect switch on.
16. Using a deep-well, 1/2” hex socket or nut driver,
turn the upper cam hex nut clockwise in one click
increments until the damper linkage tube rests
against the hex shaft. (Refer to Figure 3. )
Cambridge Air Solutions
90
S-Series Technical Manual
REFERENCE
ELECTRICAL CONTROL ENCLOSURE ISOMETRIC DRAWING
S-Series Technical Manual
91
Cambridge Air Solutions
REFERENCE
ELECTRICAL WIRING DIAGRAMS
Symbol
AF
AMP
AX1
AX
CR1
D & D1
DISC
DTS
EAT
FR
FSR
Description
Air Flow Switch
Amplifier Solid State
Auxiliary Contact
Auxiliary Contact
Control Relay
Damper Motor & End Switch
Service Disconnect Non - Fused
Discharge Temperature Sensor
Entering Air Thermostat
Flame Rod
Flame Safeguard Relay
Cambridge Air Solutions
Symbol
FU1
FU2
HL
IG
L1
L2
L3
LTC
M
MS
MV
400,000 BTU & BELOW
EDL Controls
Description
Fuse 24 Volt Control
Fuse 120 Volt Control
High Limit
Igniter
Light - Alarm
Light - Fan
Light - Heat
Low Temperature Cutout
Motor
Motor Starter
Modulating Valve
92
Symbol
OL
PCB
RTS
R1
SOV
SW1
SW2
SW3
T1
T2
TS
Description
Overload Relay
Printed Circuit Board
Remote Temperature Sensor
Relay - Gas Valve
Shut-Off Valve - Gas
Service Switch - Fan
Service Switch - Heat
Switch - Fan/Off/Heat
Multi-Tap Transformer (24 & 120 Volt)
Class 2 Transformer (24 Volt)
Temperature Sensor - LTC/EAT
S-Series Technical Manual
400,000 BTU & ABOVE
EDL Controls
Symbol
AF
AMP
AX1
AX
CR1
D & D1
DISC
DTS
EAT
FR
FSR
Description
Air Flow Switch
Amplifier Solid State
Auxiliary Contact
Auxiliary Contact
Control Relay
Damper Motor & End Switch
Service Disconnect Non - Fused
Discharge Temperature Sensor
Entering Air Thermostat
Flame Rod
Flame Safeguard Relay
S-Series Technical Manual
Symbol
FU1
FU2
HL
IG
L1
L2
L3
LTC
M
MV
MS
Description
Fuse 24 Volt Control
Fuse 120 Volt Control
High Limit
Igniter
Light - Alarm
Light - Fan
Light - Heat
Low Temperature Cutout
Motor
Modulating Valve
Motor Starter
93
Symbol
OL
RTS
R1
SOV
SSV
SW1
SW2
SW3
SW4
T1
T2
Description
Overload Relay
Remote Temperature Sensor
Relay - Gas Valve
Shut-Off Valve - Gas
Safety Shut-Off Valve - Gas
Service Switch - Fan
Service Switch - Heat
Switch - Fan/Off/Heat
Switch - SOV Leak Test
Multi-Tap Transformer (24 & 120 Volt)
Class 2 Transformer (24 Volt)
Cambridge Air Solutions
400,000 BTU & ABOVE
EDSM Controls
Symbol
AF
AMP
AX1
AX
CR1
D & D1
DISC
DTS
EAT
FR
FSR
FU1
Description
Air Flow Switch
Amplifier Solid State
Auxiliary Contact
Auxiliary Contact
Control Relay
Damper Motor & End Switch
Service Disconnect Non - Fused
Discharge Temperature Sensor
Entering Air Thermostat
Flame Rod
Flame Safeguard Relay
Fuse 24 Volt Control
Cambridge Air Solutions
Symbol
FU2
HL
IG
L1
L2
L3
LFS
LTC
M
MS
MV
OL
Description
Fuse 120 Volt Control
High Limit
Igniter
Light - Alarm
Light - Fan
Light - Heat
Low Fire Start
Low Temperature Cutout
Motor
Motor Starter
Modulating Valve
Overload Relay
94
Symbol
R1
RC
RTS
SOV
SSV
STS
SW1
SW2
SW3
SW4
T1
T2
Description
Relay - Gas Valve
Calibration Resistor
Remote Temperature Sensor
Shut-Off Valve - Gas
Safety Shut-Off Valve - Gas
Space Temperature Selector
Service Switch - Fan
Service Switch - Heat
Switch - Fan/Off/Heat
Switch - SOV Leak Test
Multi-Tap Transformer (24 & 120 Volt)
Class 2 Transformer (24 Volt)
S-Series Technical Manual
400,000 BTU & ABOVE
EDSM/TP Controls
Temperature Setback System
Temperature Averaging System
Symbol
AF
AMP
AX1
AX
CR1
D & D1
DISC
DTS
EAT
FR
FSR
FU1
FU2
Description
Air Flow Switch
Amplifier Solid State
Auxiliary Contact
Auxiliary Contact
Control Relay
Damper Motor & End Switch
Service Disconnect Non - Fused
Discharge Temperature Sensor
Entering Air Thermostat
Flame Rod
Flame Safeguard Relay
Fuse 24 Volt Control
Fuse 120 Volt Control
S-Series Technical Manual
Symbol
HL
IG
L1
L2
L3
LFS
LTC
M
MS
MV
OL
OTS
RC
Description
High Limit
Igniter
Light - Alarm
Light - Fan
Light - Heat
Low Fire Start
Low Temperature Cutout
Motor
Motor Starter
Modulating Valve
Overload Relay
Override Timer Switch
Calibration Resistor
95
Symbol
RTSS
R1
SOV
SSV
STS
SW1
SW2
SW3
SW4
T1
T2
TPS
TSS
Description
Remote Temperature Sensor
Relay - Gas Valve
Shut-Off Valve - Gas
Safety Shut-Off Valve - Gas
Space Temperature Selector
Service Switch - Fan
Service Switch - Heat
Switch - Fan/Off/Heat
Switch - SOV Leak Test
Multi-Tap Transformer (24 & 120 Volt)
Class 2 Transformer (24 Volt)
Tamperproof Sensor
Programmable Thermostat/Timer
Cambridge Air Solutions
400,000 BTU & ABOVE
EDR Controls
Symbol
AF
AMP
AX1
AX
CR1
D & D1
DISC
DTS
EAT
FR
FSR
FU1
Description
Air Flow Switch
Amplifier Solid State
Auxiliary Contact
Auxiliary Contact
Control Relay
Damper Motor & End Switch
Service Disconnect Non - Fused
Discharge Temperature Sensor
Entering Air Thermostat
Flame Rod
Flame Safeguard Relay
Fuse 24 Volt Control
Cambridge Air Solutions
Symbol
FU2
HL
IG
L1
L2
L3
LFS
LTC
M
MS
MV
OL
Description
Fuse 120 Volt Control
High Limit
Igniter
Light - Alarm
Light - Fan
Light - Heat
Low Fire Start
Low Temperature Cutout
Motor
Motor Starter
Modulating Valve
Overload Relay
96
Symbol
RHA
RTS
R1
SOV
SSV
SW1
SW2
SW3
SW4
T1
T2
TS
Description
Remote Heat Adjust
Remote Temperature Sensor
Relay - Gas Valve
Shut-Off Valve - Gas
Safety Shut-Off Valve - Gas
Service Switch - Fan
Service Switch - Heat
Switch - Fan/Off/Heat
Switch - SOV Leak Test
Multi-Tap Transformer (24 & 120 Volt)
Class 2 Transformer (24 Volt)
Temperature Sensor - LTC/EAT
S-Series Technical Manual
REFERENCE
REMOTE CONTROL STATION ELECTRICAL CONNECTION DIAGRAM
S-Series Technical Manual
97
Cambridge Air Solutions
REFERENCE
BUILDING AUTOMATION SYSTEM
Cambridge Air Solutions
98
S-Series Technical Manual
REFERENCE
GAS TRAIN DRAWINGS
TO BURNER
HAND SHUT-OFF VALVE
MANOMETER TAP FOR
MANIFOLD PRESSURE READING
LOW FIRE
ADJUSTMENT SCREW
ELECTRIC SHUT-OFF VALVE
(REDUNDANT VALVE WITH
MANIFOLD PRESSURE REGULATOR)
MODULATING VALVE
Under 400 MBH
CSA Certified1
FM Compliant2
XL GAPS Compliant3
MANIFOLD PRESSURE
ADJUSTMENT SCREW
MANOMETER TAP FOR UNIT
SUPPLY PRESSURE READING
HAND SHUT-OFF VALVE
TO BURNER
HAND SHUT-OFF VALVE
MANOMETER TAP FOR
MANIFOLD PRESSURE READING
LOW FIRE
ADJUSTMENT SCREW
MANOMETER TAP FOR
VALVE LEAK TEST
ELECTRIC SHUT-OFF VALVE
(SOV)
MANIFOLD PRESSURE
ADJUSTMENT SCREW
MODULATING VALVE
Over 400 MBH
Low Pressure
CSA Certified1
XL GAPS Compliant3
ELECTRIC SHUT-OFF VALVE
MANIFOLD PRESSURE REGULATOR
(SSV)
MANOMETER TAP FOR UNIT
SUPPLY PRESSURE READING
HAND SHUT-OFF VALVE
TO BURNER
HAND SHUT-OFF VALVE
LOW FIRE & MANIFOLD PRESSURE
ADJUSTMENT SCREWS (UNDER COVER)
MANOMETER TAP FOR
MANIFOLD PRESSURE READING
MANOMETER TAP FOR
VALVE LEAK TEST
ELECTRIC SHUT-OFF VALVE
(SOV)
MODULATING REGULATING VALVE
Over 400 MBH
High Pressure
CSA Certified1
ELECTRIC SHUT-OFF VALVE
(SSV)
MANOMETER TAP FOR UNIT
SUPPLY PRESSURE READING
HAND SHUT-OFF VALVE
Certified by CSA International to comply with ANSI Standard Z83.4/CSA3.7
Complies with Factory Mutual insurance requirements
3
Complies with XL Insurance Global Asset Protection Services requirements
1
2
S-Series Technical Manual
99
Cambridge Air Solutions
REFERENCE
GAS TRAIN DRAWINGS
TO BURNER
HAND SHUT-OFF VALVE
MANUAL RESET SWITCH
MANOMETER TAP FOR
MANIFOLD PRESSURE READING
HIGH GAS PRESSURE SWITCH
LOW FIRE
ADJUSTMENT SCREW
ELECTRIC SHUT-OFF VALVE
w/ VISUAL INDICATOR
MANOMETER TAP FOR
VALVE LEAK TEST
MANIFOLD PRESSURE
ADJUSTMENT SCREW
MODULATING VALVE
Over 400 MBH
With Discharge Damper
and without Filter Section
Low Pressure
CSA Certified1
FM Compliant2
MANIFOLD PRESSURE REGULATOR
(SSV)
ELECTRIC SHUT-OFF VALVE
(SOV)
ELECTRIC SHUT-OFF VALVE
MANOMETER TAP FOR UNIT
SUPPLY PRESSURE READING
HAND SHUT-OFF VALVE
TO BURNER
HAND SHUT-OFF VALVE
HIGH GAS PRESSURE SWITCH
MANUAL RESET SWITCH
ELECTRIC SHUT-OFF VALVE
w/ VISUAL INDICATOR
MANOMETER TAP FOR
MANIFOLD PRESSURE READING
MANOMETER TAP FOR
VALVE LEAK TEST
LOW FIRE & MANIFOLD PRESSURE
ADJUSTMENT SCREWS (UNDER COVER)
MODULATING REGULATING VALVE
ELECTRIC SHUT-OFF VALVE
Over 400 MBH
With Discharge Damper
and without Filter Section
High Pressure
CSA Certified1
FM Compliant2
1
2
(SSV)
ELECTRIC SHUT-OFF VALVE
(SOV)
MANOMETER TAP FOR UNIT
SUPPLY PRESSURE READING
HAND SHUT-OFF VALVE
Certified by CSA International to comply with ANSI Standard Z83.4/CSA3.7
Complies with Factory Mutual insurance requirements
Cambridge Air Solutions
100
S-Series Technical Manual
REFERENCE
GAS TRAIN DRAWINGS
TO BURNER
HAND SHUT-OFF VALVE
MANUAL RESET SWITCH
HIGH GAS PRESSURE SWITCH
MANOMETER TAP FOR
MANIFOLD PRESSURE READING
LOW FIRE
ADJUSTMENT SCREW
MODULATING VALVE
MANOMETER TAP FOR
VALVE LEAK TEST
MANIFOLD PRESSURE
ADJUSTMENT SCREW
MANIFOLD PRESSURE REGULATOR
Over 400 MBH
Without Discharge Damper
or with Filter Section
Low Pressure
CSA Certified1
FM Compliant2
MANOMETER TAP FOR UNIT
SUPPLY PRESSURE READING
ELECTRIC SHUT-OFF VALVE
W/ VISUAL INDICATOR
(SSV)
HAND SHUT-OFF VALVE
ELECTRIC SHUT-OFF VALVE
W/ VISUAL INDICATOR
(SOV)
EXTERNAL GAS TRAIN ENCLOSURE
(ROOF SUPPORT BY OTHERS)
TO BURNER
MANOMETER TAP FOR
MANIFOLD PRESSURE READING
HAND SHUT-OFF VALVE
MANUAL RESET SWITCH
HIGH GAS PRESSURE SWITCH
MANOMETER TAP FOR
VALVE LEAK TEST
MANIFOLD PRESSURE & LOW FIRE
ADJUSTMENT SCREWS (UNDER COVER)
Over 400 MBH
Without Discharge Damper
or with Filter Section
High Pressure
CSA Certified1
FM Compliant2
1
2
MODULATING REGULATING VALVE
MANOMETER TAP FOR UNIT
SUPPLY PRESSURE READING
ELECTRIC SHUT-OFF VALVE
W/ VISUAL INDICATOR
(SSV)
HAND SHUT-OFF VALVE
ELECTRIC SHUT-OFF VALVE
W/ VISUAL INDICATOR
(SOV)
EXTERNAL GAS TRAIN ENCLOSURE
(ROOF SUPPORT BY OTHERS)
Certified by CSA International to comply with ANSI Standard Z83.4/CSA3.7
Complies with Factory Mutual insurance requirements
S-Series Technical Manual
101
Cambridge Air Solutions
REFERENCE
GAS TRAIN DRAWINGS
TO BURNER
HAND SHUT-OFF VALVE
MANUAL RESET SWITCH
MANOMETER TAP FOR
MANIFOLD PRESSURE READING
HIGH GAS PRESSURE SWITCH
LOW FIRE
ADJUSTMENT SCREW
MANOMETER TAP FOR
VALVE LEAK TEST
MANIFOLD PRESSURE
ADJUSTMENT SCREW
MODULATING VALVE
MANIFOLD PRESSURE REGULATOR
(SSV)
ELECTRIC SHUT-OFF VALVE
ELECTRIC SHUT-OFF VALVE
Over 400 MBH
Low Pressure
CSA Certified1
XL GAPS Compliant3
(SOV)
MANOMETER TAP FOR UNIT
SUPPLY PRESSURE READING
HAND SHUT-OFF VALVE
TO BURNER
HAND SHUT-OFF VALVE
MANOMETER TAP FOR
MANIFOLD PRESSURE READING
MANUAL RESET SWITCH
HIGH GAS PRESSURE SWITCH
MANOMETER TAP FOR
VALVE LEAK TEST
LOW FIRE & MANIFOLD PRESSURE
ADJUSTMENT SCREWS (UNDER COVER)
MODULATING REGULATING VALVE
ELECTRIC SHUT-OFF VALVE
(SSV)
ELECTRIC SHUT-OFF VALVE
Over 400 MBH
High Pressure
CSA Certified1
XL GAPS Compliant3
(SOV)
MANOMETER TAP FOR UNIT
SUPPLY PRESSURE READING
HAND SHUT-OFF VALVE
Certified by CSA International to comply with ANSI Standard Z83.4/CSA3.7
Complies with Factory Mutual insurance requirements
3
Complies with XL Insurance Global Asset Protection Services requirements
1
2
Cambridge Air Solutions
102
S-Series Technical Manual
INDIVIDUAL COMPONENT DESCRIPTIONS
REMOTE CONTROL STATIONS
REMOTE CONTROL STATION
COMPONENTS
REMOTE CONTROL STATION - SECURITY
(RCS-S)
CLOGGED FILTER LIGHT (CF)
The RCS-S is a lockable NEMA 1
enclosure (9”W x 14”H x 5”D) equipped
with a three position key-lock selector
switch (Summer Ventilation - Off Heating); an Operating Electronic
Thermostat (OET); and indicating lights
for blower operation (green), burner operation (red),
and reset (amber).
The clogged filter light is an alarm light mounted in
the remote control station to indicate a clogged filter
condition. Includes an adjustable pressure switch
mounted in the electrical control enclosure to monitor
the pressure drop across the filters.
EXHAUST FAN INTERLOCK (EFI)
The operator can control the heater from this panel
provided the heater mounted disconnect is in the
”ON” position and the service switches are in the
”REMOTE” position. The OET utilizes an encapsulated thermistor to sense space temperature. The
adjustable differential is set by the selection of the ON
and OFF temperatures. See instructions for the OET
(page 64).
An exhaust fan interlock is used to interlock the makeup air heater as a slave to an exhaust fan. Terminals are
provided in the remote control station for wiring of dry
contacts (by others).
MANUAL MAKE-UP AIR SWITCH (MMS)
A manual make-up air toggle switch is used to
manually turn the heater on and off. It is either
mounted on the exterior of the door of the remote
control station or mounted inside for tamperproof
applications.
TEMPERATURE SETBACK SYSTEM
(TSS)
The TSS is a lockable NEMA 1 enclosure
(9”W x 14”H x 5”D) equipped with a three
position selector switch (Summer
Ventilation - Off - Heating); a combination
seven day programmable timer and
thermostat; an override timer; and
indicating lights for blower operation (green), burner
operation (red), and reset (amber).
The operator can control the heater from this panel
provided the heater mounted disconnect is in the
”ON” position and the service switches are in the
”REMOTE” position. The TSS utilizes an encapsulated
thermistor to sense space temperature. The adjustable
differential is set by the selection of the ON and OFF
temperatures. This control can accommodate separately
programmed schedules for both the ventilation and
heating modes. See the operating and programming
instructions for the TSS Controller (page 66).
S-Series Technical Manual
NON-ADJUSTABLE THERMOSTAT (TTP)
The non-adjustable thermostat is a fixed temperature,
solid state, epoxy sealed thermostat with a specified
temperature setpoint, either: 41°F, 50°F, 55°F, 60°F, or
65°F. It is wired between terminals Z1 and Z2.
TEMPERATURE AVERAGING SYSTEM
(TAS-2)
The TAS-2 option is used in
conjunction with the RCS-S or TSS to
average the space temperature between
two distant points within a facility. It
consists of four thermistors which are
wired in
a series/parallel combination in order to simulate a
single thermistor response.
103
Cambridge Air Solutions
REMOTE TEMPERATURE SENSOR (RTS)
The thermistor is wired to the remote
temperature sensor terminal block. If
remote location of the sensor is desired,
the connecting cable must be wired
between the thermistor and this point.
The thermistor enclosure (SH-1) is
packed in the remote control station for shipment. It
can be mounted on the exterior sides or bottom of the
remote control station or a remote location within 500
feet using 18 gauge stranded, twisted-pair, shielded
cable.
GAS CONTROL SYSTEMS
ELECTRONIC DISCHARGE-LOCAL (EDL)
The EDL temperature control system
utilizes Maxitrol’s Series 14
modulation controls. The discharge
temperature sensor, which is
mounted in the discharge, transmits a
resistance signal back to the
amplifier that corresponds to the
discharge temperature. The amplifier
creates a voltage output to drive the modulating valve
to maintain the preselected temperature that is set on
the dial located on the amplifier. This control permits
adjustment of the discharge temperature (110 to 160°F)
from inside the heater control enclosure.
ELECTRONIC DISCHARGE-REMOTE (EDR)
The EDR temperature control
system utilizes Maxitrol’s Series 14
modulation controls. The discharge
temperature sensor, which is
mounted in the discharge, transmits
a resistance signal back to the
amplifier that corresponds to the
discharge temperature. The amplifier creates a voltage
output to drive the modulating valve to maintain the
preselected temperature that is set on the Remote Heat
Adjust (RHA).
Heaters which are specified with a temperature rise of
less than 130˚F are supplied with a single adjusting
knob on the dial face of the RHA. This control permits
manual adjustment of the discharge air temperature
from 55 to 130˚F. The override temperature selector
dial, which is visible from the top of the RHA control,
increases the discharge temperature above the setting
on the dial face by the increment selected (10 to 40˚F)
Cambridge Air Solutions
104
when a jumper or switch contact is provided across
terminals 20 and 22.
Heaters which are specified with a temperature rise
above 130˚F are supplied with dual adjusting knobs on
the dial face of the RHA. This control permits manual
adjustment of the discharge temperature from 55 to
105˚ or 120 to 160˚F. A jumper or switch contact is
required across terminals 20 and 22 to activate the
higher temperature selection.
ELECTRONIC DISCHARGE-SPACE
MODULATION (EDSM)
The EDSM temperature control
system utilizes Maxitrol’s Series
44 modulation controls. The Space
Temperature Selector (STS) is set
to the desired space temperature
and it transmits a resistance output
to the amplifier (AMP) to control
the discharge temperature. The
discharge temperature sensor (DTS), which is mounted
in the discharge, transmits a resistance signal back to
the amplifier that corresponds to the discharge
temperature. The amplifier creates a voltage output to
drive the modulating valve (MV) to maintain the
selected space temperature by controlling the heater
output between the MIN and MAX setting on the
amplifier. The MIN dial setting determines the
minimum discharge temperature the heater will deliver
(40 to 80˚F). The MAX dial setting determines the
maximum discharge temperature the heater will deliver
(80 to 160˚F). When the space temperature drifts from
the STS setpoint by more than 3˚F, the modulating
valve is driven to the MIN or MAX discharge
temperature, as applicable.
ELECTRONIC DISCHARGE-SPACE
MODULATION/TAMPER PROOF (EDSM/TP)
The EDSM/TP temperature control system
functions identical to the EDSM control
system. The difference is the STS is replaced
with two devices. The adjustable temperature
selector is typically mounted inside the
remote control station and the non-adjustable
space sensor (RTSS) is mounted in the space.
S-Series Technical Manual
ELECTRONIC DISCHARGE-SPACE
MODULATION/HAZARDOUS AREA
DISCHARGE TEMPERATURE SENSOR
(DTS)
GAS CONTROL COMPONENTS
FLAME ROD (FR)
The DTS is mounted in the discharge of
the heater. It senses the average
discharge temperature and transmits a
resistance signal back to the amplifier
that corresponds to the discharge
temperature.
The Hazardous Area temperature control system
functions identical the EDSM/TP, except the space
sensor (TS244A) is replaced by a space sensor with
epoxy coated circuitry (ES225A). The standard remote
control station is not suitable for hazardous areas and
would need to be mounted outside of the hazardous area.
The flame rod senses the presence
of flame and signals the flame
safeguard relay. The presence of
flame is detected by the flame
rectification of the AC signal that
is supplied to the flame rod thus
creating the DC response. The resulting current flow
produced can be measured with a DC microammeter.
The reading should be steady and between 2.0 and 6.0
microamps (mA).
AMPLIFIER (AMP)
The amplifier creates a voltage output
to drive the modulating valve to
maintain the selected discharge
temperature. On EDL control systems,
the discharge temperature is set at the
amplifier. On EDR control systems,
the discharge temperature is set on the
RHA. On EDSM control systems, the range of the
discharge temperature is set at the amplifier, however,
the STS controls when more or less heat is required.
FLAME SAFEGUARD RELAY (FSR)
The flame safeguard relay supplies 24
Volts AC to the igniter for 4 seconds
before the gas valve is energized. If the
burner does not light (flame is not
established within 7 seconds), this
control will lock out gas flow until the control is reset.
If flame signal is lost during burner operation, the
control will allow one retry for ignition.
COMBINATION VALVE
The combination valve serves as a
manifold pressure regulator and
redundant gas shut-off valve. This
control is typically used for gas
capacities below 400,000 Btu/hr. The
valve operates on 24 Volts AC
power. The combination valve is rated for a maximum
gas supply pressure of 14” WC.
HIGH/LOW GAS PRESSURE SWITCH
(HGP, LGP)
DISCHARGE AIR TEMPERATURE
SAMPLING BOX
This gas pressure switch is a manual
reset safety device to lock out the
burner operation should large gas
pressure fluctuations occur. The high
gas pressure switch should be set 3”
WC above manifold gas pressure. The
low pressure switch should be set at 2”
WC. The adjustment screw is located under the top
plate. The low gas pressure switch will have to be reset
whenever gas supply has been interrupted.
The discharge air temperature sampling box is located on the side
of the discharge, and is accessible
from the electrical control enclosure
side of the unit. The sampling box
houses the high limit (HL) and the
discharge temperature sensor (DTS).
This box should not be tampered with
unless performing the Calibration
Procedures (pages 60–62).
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HIGH PRESSURE REGULATOR (HPR)
The HPR option is required when the
gas supply pressure exceeds the
nameplate rating for the heater.
Unless otherwise specified, the HPR
assembly is also furnished with a high
gas pressure manual shut-off valve
and a tap for measuring the upstream gas pressure. The
HPR must be a positive lock-up type regulator which
must be vented to outdoors. It is sized according to the
gas supply pressure and the capacity requirements of
the heater.
INTERMITTENT/CONTINUOUS CONTROL
The Intermittent/Continuous Control allows the burner
input to be modulated to be operated continuously at
modulating discharge temperature for make-up air (see
EDSM on page 68) or operated intermittently based on
a thermostat at maximum discharge temperature (see
EDL on page 68) for space heating.
Requires EDSM controls and a signal to switch
between modes (Exhaust Fan Interlock, Temperature
Setback System, Manual Make-Up Air Switch, etc.)
IGNITER (IG)
The hot surface igniter is the
ignition source for lighting the gas
in the burner. It is made of silicon
carbide which is very fragile. Care
should be used in handling. It
operates on 24 Volts and the current
ranges from 1.3 to 1.7 amps. It will reach temperatures
in excess of 2400˚F during the ignition trial. It is
furnished with a vinyl sleeve for shock mounting and
sealing in the mounting tube.
LEAK TEST FACILITY (SW4)
The leak test facility is provided on
all heaters over 400,000 Btu/hr. It
consists of a momentary switch for
the shut-off valve (SOV) in the gas
train and a gauge port between the
(SOV) and (SSV) shut-off
valve. By holding the gas valve
momentary switch closed, the (SOV)
gas valve is energized which allows
gas pressure to build on the seat of
the SSV safety shut-off gas valve.
The gauge port between valves is
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used to determine if the SOV shut-off gas valve seat is
properly sealed.
MANIFOLD PRESSURE REGULATOR
The manifold pressure regulator
controls the burner manifold
pressure. When the MR212 valve is
used, this modulating valve also
serves as the manifold pressure
regulator. The maximum gas supply
pressure rating is normally
determined by the exposed pressure rating of the
regulating device. RV61 and RV81 regulators are rated
at 1 psig; and the MR212 is rated at 5 psig. (For units
rated at 400,000 Btu/hr or below, see the combination
valve below.)
MODULATING VALVE (MV)
The MV responds to a 4 to 24 Volt
DC signal from the amplifier to
modulate the flow of gas to the
burner. On the M511 or M611
valve, the low fire adjusting screw is
located on the far side of the valve
under the dust cover. On the MR212 valve, the low fire
adjusting screw is located under the large dust cover.
The MR212 modulating valve also serves as the
manifold pressure regulator.
REMOTE HEAT ADJUSTMENT (RHA)
As discussed under the component
description for the EDR control
system, the RHA may have a single
or dual adjusting knob(s) on the dial
face. The single adjusting knob
control permits manual adjustment
of the discharge air temperature
from 55 to 130˚F. The override
temperature selector dial which is visible from the top
of the RHA control, increases the discharge
temperature above the setting on the dial face by the
increment selected when a jumper or switch contact is
provided across terminals 20 and 22.
Heaters which are specified with a temperature rise
above 130˚F are supplied with dual adjusting knobs on
the dial face of the RHA. This control permits manual
adjustment of the discharge temperature from 55 to
105˚F or 120 to 160˚F. A jumper or switch contact
is required across terminals 20 and 22 to activate the
higher temperature selection.
S-Series Technical Manual
EXHAUST FAN CONTACT (EFC)
SPACE TEMPERATURE SELECTOR (STS)
The exhaust fan contact is an auxiliary dry contact
that is mechanically interlocked to the heater’s motor
starter and is provided with terminals located in the
electrical enclosure. The EFC is typically wired into an
exhaust fan control circuit to activate the exhaust fan
as a slave to the heater.
The STS is part of the EDSM control
system. The STS senses the space
temperature and provides a resistance
signal back to the amplifier that
corresponds to the temperature
variation from setpoint. A 3˚F drift
from the set temperature will cause the
heater to modulate to the extreme end of the preset
range on the amplifier.
FUSE BLOCK (FU1, FU2)
The fuse block provides line fusing for
branch circuit protection. It is wired in
conjunction with the non-fused
disconnect switch.
HEATER COMPONENTS
AIRFLOW SWITCH (AF)
HIGH TEMPERATURE LIMIT (HL)
The airflow switch senses the pressure
drop across the burner. It is factory set
and not adjustable. It is designed to
prevent burner operation if the airflow
drops significantly below the minimum
design airflow of the heater.
The high limit opens when discharge
temperature exceeds 180˚F. This limit
must be manually reset.
MOTOR STARTER (MS, OL, AUX)
The motor starter assembly consists of
a motor starter, overload relay and
auxiliary contact. The overload relay
protects the motor from excessive
current or single phasing. If the
overload relay trips, it must be reset
manually. The auxiliary contacts are
used in the gas valve safety circuit as
an indication the blower is operating, and as an
optional exhaust fan contact for interlocking other
equipment with the operation of the heater.
DAMPER MOTOR (D, D1)
The damper motor operates on 24
Volts AC and switches power to the
motor starter when the damper
blades are fully open by the closure
of the damper end switch. The
damper end switch is an adjustable
internal auxiliary switch which has been factory set to
operate when the damper is fully open. The damper
motor will power closed when the heater cycles off.
The damper motor will not close unless the blower
service switch is in the ”REMOTE” position. For
detailed instructions refer to Damper Motor
Replacement & Adjustment (page 89).
MULTI-FUNCTIONAL PC BOARD
The multi-functional PC board provides
five (5) separate functions as follows:
DISCONNECT SWITCH (DISC)
1) Blower Relay (CR1) which is energized
on ”call for blower” from the remote
control station.
The disconnect switch is provided on all
heaters and includes the disconnect rod and
lockable operating knob. The disconnect
switch must be in the ”OFF” position to
gain access to the control enclosure. Once the control
enclosure is open, experienced service technicians may
activate the electrical circuit by twisting the disconnect
rod clockwise to assist in troubleshooting. The
disconnect rod must be turned back to the ”OFF”
position before attempting to secure the enclosure
door.
S-Series Technical Manual
2) The LTC (Low Temperature Cutout) circuit
functions to shut down the blower in approximately
31/2 minutes if either of the following occurs: (a) The
inlet temperature drops below the LTC setpoint (40,
45, 50, or 55˚F) in the ventilation mode; or (b) the gas
valve fails to remain energized during a heating cycle.
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3) The EAT (Entering Air Thermostat) circuit
functions automatically to turn off the burner when the
outdoor temperature reaches the EAT setpoint (45, 50,
55, 57.5, 60, 62, 64, 66, 68 or 70˚F).
4) The PT (Purge Timer) circuit function is preset at
the factory to provide four air changes within the heater
cabinet prior to an ignition attempt (normally set at 4 or
8 seconds). If inlet ducting is attached to the heater, the
delay time can be increased to 8, 16, or 32 seconds, as
applicable.
THERMISTOR SENSOR
The thermistor enclosure is packed inside the Remote
Control Station for shipment. It can be mounted on the
exterior sides or bottom of the Remote Control Station
(see Figure 1). It can also be mounted in a remote location within 500 feet of the Remote Control Station using
18 gauge stranded, twisted-pair, shielded cable. The
thermistor is wired to the TEMP. SENSOR terminal
block on the thermostat.
5) The patented LFS (Low Fire Start) circuit function
is provided to limit the initial heater firing for the
first 15 seconds of a heating cycle. The voltage to the
modulating valve is adjusted between 9 and 13 Volts DC
by an adjustable potentiometer on the PC board.
SERVICE SWITCH (SW1, SW2, SW3)
The service switches are mounted in the
electrical control enclosure. In the
”LOCAL” or ”OFF” position, the service
technician has local control of the heater.
These switches must be placed in the
”REMOTE” position for normal control
from the remote control station.
TRANSFORMER (T1, T2)
Heaters supplied with an output of
greater than 400,000 Btu/hr are
furnished with a dual voltage
transformer unless the supply voltage
is 115 volts. The transformer
furnished depends on the supply
voltage (208, 230, 460 or 575 volts). This transformer
provides the secondary control voltage of 24 and 115
Volts. Heaters rated below 400,000 Btu/hr or supplied
for 115 Volts are furnished with the 24 Volt secondary
transformer only. Secondary fusing is provided in all
Class I transformer circuits to protect the downstream
components from short circuit. Fuse sizing is as follows:
FNM-6.25 for 150 VA 24 Volt; FNM-1.6 for 150 VA
115 Volt; and FNM-2.25 for 200 VA 115 Volt. Consult
the heater wiring diagram to identify the proper fusing.
Do not increase the fuse rating over that which is
specified.
Figure 1
THERMISTOR INSTALLATION
(See Figure 2)
1. Insert the star bushing through the opening in the
enclosure.
2. Run the thermistor leads through the star bushing.
3. Attach the cover to the enclosure over the thermistor
sensor.
4. Separate and strip the ends of the lead wires 3/8".
5. Open the terminal blocks for the sensor connections.
Figure 2
6. Insert the lead wires and close the terminal blocks to
the locked position.
NOTE: For Figure
remote1 sensors connected with shielded
cable, ground the shield at the thermostat end only.
Figure 3
Figure 2
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S-Series Technical Manual
Figure 2
TEMPERATURE AVERAGING (TAS-2)
OPTION
(See Figure 3)
The TAS-2 option allows one thermostat to have two
sensing locations. Each enclosure has two thermistor
sensors prewired in series (see A). The sensor leads are
then connected to the thermostat in parallel (see B). The
thermostat display will show the average of the temperatures at the two sensing locations. The TAS-2 is a unique
application. Consult the design drawing and/or your
Cambridge Representative for placement assistance.
Figure 3
ANSI/ASHRAE/IESNA STANDARD 90.1
Overview
Energy efficient, Genuine Cambridge® direct
gas-fired heating equipment can comply with the
requirements of ANSI/ASHRAE/IESNA Standard
90.1-2010. Compliance is shown on the Cambridge
heater nameplate.
Purpose of ASHRAE Standard 90.1
ASHRAE Standard 90.1 provides minimum
requirements for the energy efficient design and
construction of new commercial buildings in the
United States. The standard covers the entire
building, setting minimum equipment efficiency
levels for components that may be used, rather than
setting standards for component manufacturing.
The provisions of this standard do not apply to
single family houses, low rise residential buildings
and buildings (or portions of buildings) that use
energy primarily for industrial, manufacturing or
commercial processes.
Compliance Requirements:
The following are required for Cambridge heaters to
comply with Standard 90.1:
• Controls (Section 6.4.3)
Total airflow of all heaters less than 10,000 cfm
- The Cambridge TSS Controller will meet the
standard. A properly configured building DDC
system with the necessary programming for zone
control, automatic shutdown and setback can also
meet the standard.
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Total airflow of all heaters exceeds 10,000
cfm - The Cambridge TSS Controller with
optimum start control will meet the standard. A
properly configured building DDC system with
the necessary programming for zone control,
automatic shutdown, setback and optimum start
can also meet the standard.
Units intended to operate continuously - No
special controls are required to meet the standard.
amper (Section 6.4.3.4.3)
•D
A damper is required on each heater. The
Cambridge Motorized Discharge Damper (MDD)
will meet the standard.
•L
abeling (Section 6.4.1.5.1)
The heater must be labeled to indicate that it
complies with the requirements of the standard.
The nameplate of Cambridge heaters includes the
required labeling.
• Efficiency
(Section 6.4.1.3)
Direct gas-fired heating equipment has no
minimum efficiency requirement. However
Cambridge certifies that its equipment has a
100% combustion efficiency (Ec) and a 92%
thermal efficiency (Et).
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Cambridge Air Solutions
760 Long Road Crossing Dr., Chesterfield, MO 63005
Phone: (636) 532-2233 (800) 899-1989, Fax: (636) 530-6133
www.cambridgeair.com