installation instructions - R-Mech

INSTALLATION
INSTRUCTIONS
2010 Lennox Industries Inc.
Dallas, Texas, USA
Merit® Series 13ACX Units
AIR CONDITIONER
506374−01
07/10
Supersedes 03/10
Litho U.S.A.
TABLE OF CONTENTS
RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
WARNING
Improper installation, adjustment, alteration, service or
maintenance can cause personal injury, loss of life, or
damage to property.
Installation and service must be performed by a licensed
professional installer (or equivalent) or a service agency.
IMPORTANT
The Clean Air Act of 1990 bans the intentional venting of
refrigerant (CFCs, HCFCs and HFCs) as of July 1, 1992.
Approved methods of recovery, recycling or reclaiming
must be followed. Fines and/or incarceration may be
levied for noncompliance.
Shipping and Packing List . . . . . . . . . . . . . . . . . . . . . . . . 1
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Unit Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Typical Unit Parts Arrangement . . . . . . . . . . . . . . . . . . . 2
Model Number Identification . . . . . . . . . . . . . . . . . . . . . . 3
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Operating Gauge Set and Service Valves . . . . . . . . . . . 3
Recovering Refrigerant from Existing System . . . . . . . 5
New Outdoor Unit Placement . . . . . . . . . . . . . . . . . . . . . 6
New or Replacement Line Set . . . . . . . . . . . . . . . . . . . . . 6
Metering Devices and Flushing the System . . . . . . . . 10
Testing for Leaks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Evacuating the System . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Electrical Connections . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Servicing Unit Delivered Void of Charge . . . . . . . . . . . 16
Unit Start−Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
System Refrigerant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Removing and Installing Louvers . . . . . . . . . . . . . . . . . 22
System Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Start−Up and Performance Checklist . . . . . . . . . . . . . . 24
Shipping and Packing List
IMPORTANT
This unit must be matched with an indoor coil as
specified in Lennox Engineering Handbook. Coils
previously charged with HCFC−22 must be flushed.
WARNING
Electric Shock Hazard. Can cause injury
or death. Unit must be grounded in
accordance with national and local
codes.
Line voltage is present at all components
when unit is not in operation on units with
single-pole contactors. Disconnect all
remote electric power supplies before
opening access panel. Unit may have
multiple power supplies.
07/10
*2P0710*
Check the unit for shipping damage and listed times below
are intact. If damaged, or if parts are missing, immediately
contact the last shipping carrier.
1 Assembled outdoor unit
1 Refrigerant flow control kit (Fixed Orifice)
1 Liquid line filter drier
General
13ACX, which will also be referred to in this instruction as
the outdoor unit, uses HFC−410A refrigerant. This outdoor
unit must be installed with a matching indoor unit and line
set as outlined in the Lennox 13ACX Engineering
Handbook.
This outdoor unit is designed for use in systems that use
one of the following refrigerant metering devices:
Thermal expansion valve (TXV)
Fixed orifice
Page 1
506374−01
*P506374-01*
Unit Dimensions − Inches (mm)
A
A
OUTDOOR
COIL FAN
DISCHARGE AIR
COMPRESSOR
B
SUCTION AND LIQUID
LINE CONNECTION
OPTIONAL UNIT
STANDOFF KIT (4)
(FIELD INSTALLED)
SIDE VIEW
SIDE VIEW
Model Numbers
A
B
−018
24−1/4 (616)
25−1/4 (641)
−024
24−1/4 (616)
25−1/4 (641)
−030
24−1/4 (616)
29−1/4 (743)
−036
24−1/4 (616)
29−1/4 (743)
−042
28−1/4 (724)
29−1/4 (743)
−048
28−1/4 (724)
37−1/4 (925)
−060
28−1/4 (724)
33−1/4 (845)
Typical Unit Parts Arrangement
NOTE PLUMBING LAYOUT AND COMPRESSOR TYPE MAY VARY SLIGHTLY BETWEEN
MODEL SIZES.
CONTROL
COMPRESS0R
DISCHARGE LINE
CAPACITOR
GROUND LUG
COMPRESSOR
HARNESS
CONTACTOR
OUTDOOR COIL
CUTOUT FOR HIGH
VOLTAGE CONDUIT
HIGH PRESSURE
SWITCH (S4)
CONTROL WIRE
LOOP
LIQUID LINE SERVICE VALVE
Page 2
506374−01 07/10
SUCTION LINE SERVICE VALVE
Model Number Identification
13 AC X − 024 − 230 − 2
Minor Revision Number
Nominal SEER
Voltage
230 = 208/230V−1phase−60hz
Unit Type
AC = Air Conditioner
Cooling Capacity − Tons
018 = 1.5
024 = 2
030 = 2.5
036 = 3
042 = 3.5
048 = 4
060 = 5
Refrigerant
X = R−410A
WARNING
IMPORTANT
This product and/or the indoor unit it is matched with may
contain fiberglass wool.
Disturbing
the
insulation
during
installation,
maintenance, or repair will expose you to fiberglass wool
dust. Breathing this may cause lung cancer. (Fiberglass
wool is known to the State of California to cause cancer.)
Fiberglass wool may also cause respiratory, skin, and
eye irritation.
Only use Allen wrenches of sufficient hardness (50Rc −
Rockwell Harness Scale minimum). Fully insert the
wrench into the valve stem recess.
Service valve stems are factory−torqued (from 9 ft−lbs for
small valves, to 25 ft−lbs for large valves) to prevent
refrigerant loss during shipping and handling. Using an
Allen wrench rated at less than 50Rc risks rounding or
breaking off the wrench, or stripping the valve stem
recess.
See the Lennox Service and Application Notes #C−08−1
for further details and information.
To reduce exposure to this substance or for further
information, consult material safety data sheets
available from address shown below, or contact your
supervisor.
IMPORTANT
Lennox Industries Inc.
P.O. Box 799900
Dallas, TX 75379−9900
To prevent stripping of the various caps used, the
appropriately sized wrench should be used and fitted
snugly over the cap before tightening.
CAUTION
When servicing or repairing HVAC components, ensure
the fasteners are appropriately tightened. Table 1 provides
torque values for fasteners.
Table 1. Torque Requirements
Physical contact with metal edges and corners
while applying excessive force or rapid motion can
result in personal injury. Be aware of, and use
caution when working near these areas during
installation or while servicing this equipment.
General Information
These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
who have jurisdiction before installation.
Operating Gauge Set and Service Valves
These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
who have jurisdiction before installation.
TORQUE REQUIREMENTS
When servicing or repairing heating, ventilating, and air
conditioning components, ensure the fasteners are
appropriately tightened. Table 1 lists torque values for
fasteners.
Parts
Recommended Torque
Service valve cap
8 ft.− lb.
11 NM
Sheet metal screws
16 in.− lb.
2 NM
Machine screws #10
28 in.− lb.
3 NM
Compressor bolts
90 in.− lb.
10 NM
Gauge port seal cap
8 ft.− lb.
11 NM
USING MANIFOLD GAUGE SET
When checking the system charge, only use a manifold
gauge set that features low loss anti−blow back fittings.
Manifold gauge set used with HFC−410A refrigerant
systems must be capable of handling the higher system
operating pressures. The gauges should be rated for use
with pressures of 0 − 800 psig on the high side and a low
side of 30" vacuum to 250 psig with dampened speed to
500 psi. Gauge hoses must be rated for use at up to 800
psig of pressure with a 4000 psig burst rating.
Page 3
13ACX SERIES
OPERATING SERVICE VALVES
The liquid and vapor line service valves are used for
removing refrigerant, flushing, leak testing, evacuating,
checking charge and charging.
Each valve is equipped with a service port which has a
factory−installed valve stem. Figure 1 provides information
on how to access and operating both angle and ball service
valves.
SERVICE VALVES
SERVICE PORT CAP
SERVICE PORT
VARIOUS TYPES
SERVICE PORT
CORE
(VALVE STEM SHOWN
CLOSED) INSERT HEX
WRENCH HERE
OPEN TO BOTH INDOOR AND
OUTDOOR UNITS
SERVICE PORT CAP
VALVE STEM
FRONT-SEATED
SERVICE PORT
SERVICE PORT
CORE
TO INDOOR
UNIT
(VALVE STEM
SHOWN OPEN)
INSERT HEX
WRENCH HERE
TO INDOOR
UNIT
TO OUTDOOR UNIT
TO OUTDOOR
UNIT
ANGLE−TYPE
SERVICE VALVE
(FRONT−SEATED
CLOSED)
STEM CAP
CLOSED TO BOTH
INDOOR AND OUTDOOR
UNITS
TO INDOOR UNIT
ANGLE−TYPE SERVICE VALVE
(BACK−SEATED OPENED)
WHEN SERVICE VALVE IS CLOSED, THE SERVICE PORT IS OPEN TO THE
LINE SET AND INDOOR UNIT.
TO OPEN ROTATE STEM
COUNTERCLOCKWISE 90°.
WHEN SERVICE VALVE IS OPEN, THE SERVICE PORT IS OPEN TO LINE SET,
INDOOR AND OUTDOOR UNIT.
SERVICE PORT CORE
SERVICE PORT CAP
STEM CAP
TO OUTDOOR UNIT
With Torque Wrench: Finger tighten and torque cap per Table 1.
Operating Angle Type Service Valve:
VALVE STEM
SERVICE PORT
A service port cap protects the service port core from contamination and
serves as the primary leak seal.
1. Remove service port cap with an appropriately sized wrench.
2. Connect gauge set to service port.
3. When testing is completed, replace service port cap and tighten as follows:
Without Torque Wrench: Finger tighten and use an appropriately
sized wrench to turn an additional 1/6 turn clockwise.
BALL (SHOWN CLOSED)
TO CLOSE ROTATE STEM
CLOCKWISE 90°.
To Access Service Port:
STEM CAP
1/6 TURN
11 12 1
2
10
9
3
4
8
7 6 5
BALL−TYPE SERVICE
VALVE
1. Remove stem cap with an appropriately sized wrench.
2. Use a service wrench with a hex−head extension (3/16" for liquid line valve sizes and 5/16" for vapor line valve
sizes) to back the stem out counterclockwise as far as it will go.
Operating Ball Type Service Valve:
1. Remove stem cap with an appropriately sized wrench.
2. Use an appropriately sized wrenched to open. To open valve, rotate stem counterclockwise 90°. To close rotate stem clockwise 90°.
Reinstall Stem Cap:
1/6 TURN
Stem cap protects the valve stem from damage and serves as the primary seal. Replace the stem cap and
tighten as follows:
With Torque Wrench: Finger tighten and then torque cap per Table 1.
Without Torque Wrench: Finger tighten and use an appropriately sized wrench to turn
an additional 1/12 turn clockwise.
11 12 1
2
10
9
3
4
8
7 6 5
NOTE A label with specific torque requirements may be affixed to the stem cap. If the label is present, use the specified torque.
Figure 1. Angle and Ball Service Valves
Page 4
506374−01 07/10
Recovering Refrigerant from Existing System
RECOVERING
REFRIGERANT FROM SYSTEM
2
1
CONNECT MANIFOLD GAUGE SET
DISCONNECT POWER
Disconnect all power to the existing outdoor unit at the service
disconnect switch or main fuse box/breaker panel.
Connect a gauge set, clean recovery cylinder and a recovery
machine to the service ports of the existing unit. Use the
instructions provided with the recovery machine to make the
connections.
MAIN FUSE BOX/
BREAKER PANEL
MANIFOLD GAUGES
RECOVERY MACHINE
SERVICE
DISCONNECT
SWITCH
LOW
CLEAN RECOVERY
CYLINDER
3
RECOVERING REFRIGERANT
HIGH
OUTDOOR UNIT
Remove existing HCFC−22 refrigerant using one of the following procedures:
IMPORTANT Some system configurations may contain higher than normal refrigerant charge due to either large internal coil volumes,
and/or long line sets.
METHOD 1:
Us this method if the existing outdoor unit is not equipped with shut−off valves, or if the unit is not operational and you plan to use the existing
HCFC−22 to flush the system.
Remove all HCFC−22 refrigerant from the existing system. Check gauges after shutdown to confirm that the entire system is completely void of
refrigerant.
METHOD 2:
Use this method if the existing outdoor unit is equipped with manual shut−off valves, and you plan to use new HCFC−22 refrigerant to flush the
system.
The following devices could prevent full system charge recovery into the outdoor unit:
Outdoor unit’s high or low−pressure switches (if applicable) when tripped can cycle the compressor OFF.
Compressor can stop pumping due to tripped internal pressure relief valve.
Compressor has internal vacuum protection that is designed to unload the scrolls (compressor stops pumping) when the pressure ratio meets
a certain value or when the suction pressure is as high as 20 psig. (Compressor suction pressures should never be allowed to go into a vacuum.
Prolonged operation at low suction pressures will result in overheating of the scrolls and permanent damage to the scroll tips, drive bearings and
internal seals.)
Once the compressor can not pump down to a lower pressure due to one of the above system conditions, shut off the vapor valve. Turn OFF the
main power to unit and use a recovery machine to recover any refrigerant left in the indoor coil and line set.
Perform the following task:
A. Start the existing HCFC−22 system in the cooling mode and close the liquid line valve.
B. Use the compressor to pump as much of the existing HCFC−22 refrigerant into the outdoor unit until the outdoor system is full. Turn the outdoor unit
main power OFF and use a recovery machine to remove the remaining refrigerant from the system.
NOTE It may be necessary to bypass the low pressure switches (if equipped) to ensure complete refrigerant evacuation.
C.
D.
When the low side system pressures reach 0 psig, close the vapor line valve.
Check gauges after shutdown to confirm that the valves are not allowing refrigerant to flow back into the low side of the system.
Page 5
13ACX SERIES
New Outdoor Unit Placement
INSTALL UNIT AWAY
FROM WINDOWS
See Unit Dimensions on Page 2 for sizing mounting slab,
platforms or supports. Refer to Figure 2 for mandatory
installation clearance requirements.
*
*
*
TWO 90 ELBOWS INSTALLED IN LINE SET
WILL REDUCE LINE SET VIBRATION
Figure 3. Outside Unit Placement
PLACING OUTDOOR UNIT ON SLAB
When installing a unit at grade level, the top of the slab
should be high enough above the grade so that water from
higher ground would not collect around the unit as
illustrated in Figure 4.
*
NOTES:
Service panel access clearance of 30 in. (762 mm) must be
maintained.
Clearance to one of the other three sides must be 36 in. (914
mm).
DISCHARGE AIR
Clearance on one of the remaining two sides may be 12 in. (305
mm) and the final side may be 6 in. (152 mm).
BUILDING
STRUCTURE
Clearance required on top of unit is 48 in. (1219 mm).
A clearance of 24 in. (610 mm) must be maintained between two
units.
Figure 2. Installation Clearances
MOUNTING
SLAB
POSITIONING CONSIDERATIONS
CAUTION
GROUND LEVEL
Figure 4. Typical Slab Mounting at Ground Level
Slab may be level or have a slope tolerance away from the
building of not more than two degrees, or 2 inches per 5
feet (51 mm per 1524 mm) as illustrated in Figure 4.
In order to avoid injury, take proper precaution when lifting heavy objects.
Consider the following when positioning the unit:
Some localities are adopting sound ordinances based
on the unit’s sound level registered from the adjacent
property, not from the installation property. Install the
unit as far as possible from the property line.
When possible, do not install the unit directly outside
a window. Glass has a very high level of sound
transmission. For proper placement of unit in relation
to a window see the provided illustration in Figure 3.
INSTALLING OUTDOOR UNIT ON ROOF
Install the unit at a minimum of 4 inches (102 mm) above
the surface of the roof. Ensure the weight of the unit is
properly distributed over roof joists and rafters. Redwood
or steel supports are recommended.
New or Replacement Line Set
This section provides information on installation or
replacement of existing line set. If line set is not being
installed or replace then proceed to Brazing Connections
on Page 9.
Page 6
506374−01 07/10
If refrigerant lines are routed through a wall, seal and
isolate the opening so vibration is not transmitted to the
building. Pay close attention to line set isolation during
installation of any HVAC system. When properly isolated
from building structures (walls, ceilings. floors), the
refrigerant lines will not create unnecessary vibration and
subsequent sounds.
Also, consider the following when placing and installing a
high−efficiency air conditioner:
REFRIGERANT LINE SET
Field refrigerant line set consists of liquid and suction lines
from the outdoor unit to the indoor unit coil. Use Lennox
L15 (braze, non−flare) series line set, or field−fabricated
refrigerant lines that meet the specifications listed below.
Table 2. Refrigerant Line Set
Model
Valve Field
Connections
Recommended Line Set
Liquid
Line
Liquid
Line
Suction
Line
L15 Line
Set
Suction
Line
−018
−024
−030
3/8 in.
(10 mm)
3/4 in.
(19 mm)
3/8 in
(10 mm)
3/4 in.
(19 mm)
L15−41
15 ft. − 50 ft.
(4.6 m −
15 m)
−036
−042
−048
3/8 in.
(10 mm)
7/8 in.
(22 mm)
3/8 in.
(10 mm)
7/8in.
(22 mm)
L15−65
15 ft. − 50 ft.
(4.6 m −
15 m)
−060
3/8 in.
(10 mm)
1−1/8 in.
(29 mm)
3/8 in.
(10 mm)
1−1/8 in.
(29 mm)
Field
Fabricated
filter drier must be installed to ensure a clean,
moisture−free system. Failure to install the filter drier will
void the warranty. A replacement filter drier is available
from Lennox. See Brazing Connections on Page 9 for
special procedures on brazing filter drier connections to
the liquid line.
BRAZE CONNECTION
POINTS
LIQUID LINE
SERVICE VALVE
LIQUID
LINE
LINE
LIQUID LINE
FILTER DRIER
OUTDOOR
UNIT
Figure 5. Typical Liquid Line Filter Drier Installation
CAUTION
NOTE Some applications may required a field provided 7/8" to
1−1/8" adapter
NOTE − When installing refrigerant lines longer than 50
feet, contact Lennox Technical Support Product
Applications for assistance or Lennox piping manual. To
obtain the correct information from Lennox, be sure to
communicate the following points:
Model (13ACX) and size of unit (e.g. −060).
Line set diameters for the unit being installed as listed
in Table 2 and total length of installation.
Number of elbows and if there is a rise or drop of the
piping.
MATCHING WITH NEW OR EXISTING INDOOR COIL
AND LINE SET
The RFC1−metering line consisted of a small bore copper
line that ran from condenser to evaporator coil. Refrigerant
was metered into the evaporator by utilizing
temperature/pressure evaporation effects on refrigerant in
the small RFC line. The length and bore of the RFC line
corresponded to the size of cooling unit.
If the 13ACX is being used with either a new or existing
indoor coil which is equipped with a liquid line which served
as a metering device (RFCI), the liquid line must be
replaced prior to the installation of the 13ACX unit.
Typically a liquid line used to meter flow is 1/4" in diameter
and copper.
LIQUID LINE FILTER DRIER INSTALLATION
The filter drier (one is shipped with each 13ACX unit) must
be field installed in the liquid line between the outdoor unit’s
liquid line service valve and the indoor coil’s metering
device (fixed orifice or TXV) as illustrated in Figure 5. This
Brazing alloys and flux contain materials which are
hazardous to your health.
Avoid breathing vapors or fumes from brazing
operations. Perform operations only in well ventilated
areas.
Wear gloves and protective goggles or face shield to
protect against burns.
Wash hands with soap and water after handling brazing
alloys and flux.
IMPORTANT
The Environmental Protection Agency (EPA) prohibits
the intentional venting of HFC refrigerants during
maintenance, service, repair and disposal of appliance.
Approved methods of recovery, recycling or reclaiming
must be followed.
IMPORTANT
If this unit is being matched with an approved line set
or indoor unit coil which was previously charged with
mineral oil, or if it is being matched with a coil which
was manufactured before January of 1999, the coil
and line set must be flushed prior to installation. Take
care to empty all existing traps. Polyol ester (POE) oils
are used in Lennox units charged with HFC−410A
refrigerant. Residual mineral oil can act as an
insulator, preventing proper heat transfer. It can also
clog the expansion device, and reduce the system
performance and capacity.
Failure to properly flush the system per the
instructions below will void the warranty.
Page 7
13ACX SERIES
LINE SET
IMPORTANT Refrigerant lines must not contact structure.
INSTALLATION
REFRIGERANT LINE SET INSTALLING
VERTICAL RUNS (NEW CONSTRUCTION SHOWN)
Line Set Isolation The following illustrations are
examples of proper refrigerant line set isolation:
NOTE Insulate liquid line when it is routed through areas where the
surrounding ambient temperature could become higher than the
temperature of the liquid line or when pressure drop is equal to or greater
than 20 psig.
REFRIGERANT LINE SET TRANSITION
FROM VERTICAL TO HORIZONTAL
ANCHORED HEAVY NYLON
WIRE TIE OR AUTOMOTIVE
MUFFLER-TYPE HANGER
IMPORTANT Refrigerant lines must not contact wall
AUTOMOTIVE
MUFFLER-TYPE HANGER
OUTSIDE WALL
LIQUID LINE
VAPOR LINE
WALL
STUD
WIRE TIE
INSIDE WALL
STRAP
WOOD BLOCK
BETWEEN STUDS
STRAP LIQUID LINE TO
VAPOR LINE
NON−CORROSIVE
METAL SLEEVE
WIRE TIE
LIQUID LINE
NON−CORROSIVE
METAL SLEEVE
WOOD BLOCK
VAPOR LINE − WRAPPED
IN ARMAFLEX
WIRE TIE
STRAP
REFRIGERANT LINE SET INSTALLING
HORIZONTAL RUNS
SLEEVE
To hang line set from joist or rafter, use either metal strapping material
or anchored heavy nylon wire ties.
WIRE TIE (AROUND
VAPOR LINE ONLY)
VAPOR LINE WRAPPED
WITH ARMAFLEX
8 FEET (2.43 METERS)
STRAPPING
MATERIAL (AROUND
VAPOR LINE ONLY)
OUTSIDE
WALL
FLOOR JOIST OR
ROOF RAFTER
LIQUID
LINE
TAPE OR
WIRE TIE
8 FEET (2.43 METERS)
PVC
PIPE
NON−CORROSIVE
METAL SLEEVE
TAPE OR
WIRE TIE
FLOOR JOIST OR
ROOF RAFTER
FIBERGLASS
INSULATION
STRAP THE VAPOR LINE TO THE JOIST
OR RAFTER AT 8 FEET (2.43 METERS)
INTERVALS THEN STRAP THE LIQUID
LINE TO THE VAPOR LINE.
NOTE Similar installation practices should be used if line set is
to be installed on exterior of outside wall.
WARNING Polyol ester (POE) oils used with HFC−410A
refrigerant absorb moisture very quickly. It is very important that the
refrigerant system be kept closed as much as possible. DO NOT
remove line set caps or service valve stub caps until you are ready
to make connections.
Figure 6. Line Set Installation
Page 8
506374−01 07/10
CAULK
BRAZING
NOTE − Use silver alloy brazing rods with five or six percent minimum silver
alloy for copper−to−copper brazing, 45 percent alloy for copper−to−brass and
copper−to−steel brazing.
CONNECTIONS
2
CAP AND CORE REMOVAL
1
CUT AND DEBUR
Cut ends of the refrigerant lines square
(free from nicks or dents) and debur the
ends. The pipe must remain round and do
not pinch end of the line.
Remove service cap and core
from both the vapor and liquid line
service ports.
USE REGULATOR TO FLOW
NITROGEN AT 1 TO 2 PSIG.
3
LOW
HIGH
ATTACHED GAUGES
A.
Connect gauge set low pressure side to liquid line service
valve.
B.
Connect gauge set center port to bottle of nitrogen with
regulator.
B
ATTACH
GAUGES
SERVICE PORT MUST BE OPEN TO ALLOW EXIT
POINT FOR NITROGEN
VAPOR LINE
SERVICE
VALVE
VAPOR LINE
OUTDOOR
UNIT
INDOOR
UNIT
NITROGEN
LIQUID LINE
4
LIQUID LINE SERVICE
VALVE
5
WRAP SERVICE VALVE
To protect components during
brazing, wrap a wet cloth around
the liquid line service valve body
and copper tube stub and use
another wet cloth underneath the
valve body to protect the base
paint.
A
FLOW NITROGEN
Flow regulated nitrogen (at 1 to 2 psig) through the refrigeration
gauge set into the valve stem port connection on the liquid line service
valve and out of the valve stem port connection on the vapor service
valve.
LOW
6
Braze the liquid line to the liquid line
service valve. Turn off nitrogen flow.
POINT FLAME AWAY FROM
SERVICE VALVE
USE REGULATOR TO
FLOW NITROGEN AT 1
TO 2 PSIG.
NITROGEN
NOTE The fixed orifice or check
expansion valve metering device at the
indoor unit will allow low pressure
nitrogen to flow through the system.
BRAZE LINE SET
HIGH
7
INSTALL SERVICE PORT CAPS ONLY
After all connections have been brazed, disconnect manifold gauge
set from service ports, cool down piping with wet rag and remove all
wrappings. Do not reinstall cores until after evacuation procedure.
Reinstall service port caps if desired to close off refrigerant ports.
WARNING Allow braze joint to cool
before removing the wet rag from the
service valve. (TEMPERATURES ABOVE
250ºF CAN DAMAGE VALVE SEALS
SERVICE PORT CORE
SERVICE PORT CAP
SERVICE PORT
IMPORTANT Connect gauge set low pressure side to vapor
line service valve and repeat procedure starting at paragraph 4
for brazing the liquid line to service port valve.
Figure 7. Brazing Connections
Page 9
13ACX SERIES
Metering Devices and Flushing the System
TYPICAL CHECK EXPANSION VALVE
REMOVAL PROCEDURE
FLUSHING
1
(Uncased Coil Shown)
LINE SET AND INDOOR COIL (1 OF 2)
TWO PIECE PATCH PLATE
(UNCASED COIL ONLY)
TYPICAL FIXED ORIFICE REMOVAL AND
REPLACEMENT PROCEDURE
DISTRIBUTOR
TUBES
(Uncased Coil Shown)
STUB END
LIQUID LINE
ORIFICE
HOUSING
CHECK
EXPANSION
VALVE
TEFLON
RING
DISTRIBUTOR TUBES
LIQUID LINE ORIFICE HOUSING
TEFLON
RING
TEFLON RING
SENSING
LINE
FIXED ORIFICE
OR
BRASS NUT
DISTRIBUTOR
ASSEMBLY
EQUALIZER
LINE
DISTRIBUTOR
ASSEMBLY
REMOVE AND DISCARD
WHITE TEFLON SEAL (IF
PRESENT)
A.
B.
LIQUID LINE
ASSEMBLY WITH
BRASS NUT
LIQUID LINE ASSEMBLY
(INCLUDES STRAINER)
On fully cased coils, remove the coil access and plumbing panels.
Remove any shipping clamps holding the liquid line and distributor
assembly.
Using two wrenches, disconnect liquid line from liquid line orifice
housing. Take care not to twist or damage distributor tubes during
this process.
Remove and discard fixed orifice, valve stem assembly if present
and Teflon washer as illustrated above.
Use a field−provided fitting to temporary reconnect the liquid line to
the indoor unit’s liquid line orifice housing.
Reverse above order to install.
C.
D.
E.
F.
2
A
1
VAPOR
LIQUID
D
CLOSED
B
LIQUID LINE SERVICE
VALVE
RECOVERY
CYLINDER
C.
D.
E.
3
FLUSHING LINE SET
The line set and indoor unit coil must be flushed with at least the
same amount of clean refrigerant that previously charged the system. Check the charge in the flushing cylinder before proceeding.
TANK
RETURN
B.
INLET
DISCHARGE
RECOVERY MACHINE
A.
B.
C.
D.
Inverted HCFC−22 cylinder with clean refrigerant to the vapor service
valve.
HCFC−22 gauge set (low side) to the liquid line valve.
HCFC−22 gauge set center port to inlet on the recovery machine with
an empty recovery tank to the gauge set.
Connect recovery tank to recovery machines per machine
instructions.
Page 10
506374−01 07/10
LIQUID
LINE
CAUTION This procedure should not be performed on systems which contain contaminants (Example compressor burn
out.
A.
C
VAPOR
LINE
On fully cased coils, remove the coil access and plumbing panels.
Remove any shipping clamps holding the liquid line and distributor assembly.
Disconnect the equalizer line from the check expansion valve equalizer line fitting on the vapor line.
Remove the vapor line sensing bulb.
Disconnect the liquid line from the check expansion valve at the liquid
line assembly.
Disconnect the check expansion valve from the liquid line orifice housing. Take care not to twist or damage distributor tubes during this process.
Remove and discard check expansion valve and the two Teflon rings.
Use a field−provided fitting to temporary reconnect the liquid line to the
indoor unit’s liquid line orifice housing.
HIGH
NEW
OUTDOOR
UNIT
OPENED
EXISTING
INDOOR
UNIT
A.
B.
G.
H.
GAUGE
MANIFOLD
LOW
VAPOR LINE
SERVICE VALVE
SENSING BULB
F.
CONNECT GAUGES AND EQUIPMENT FOR
FLUSHING PROCEDURE
INVERTED HCFC−22
CYLINDER CONTAINS
CLEAN HCFC−22 TO BE
USED FOR FLUSHING.
MALE EQUALIZER
LINE FITTING
C.
D.
B
Set the recovery machine for liquid recovery and start the recovery machine. Open the gauge set valves to allow the recovery
machine to pull a vacuum on the existing system line set and indoor unit coil.
Invert the cylinder of clean HCFC−22 and open its valve to allow
liquid refrigerant to flow into the system through the vapor line
valve. Allow the refrigerant to pass from the cylinder and through
the line set and the indoor unit coil before it enters the recovery
machine.
After all of the liquid refrigerant has been recovered, switch the
recovery machine to vapor recovery so that all of the HCFC−22
vapor is recovered. Allow the recovery machine to pull down to 0
the system.
Close the valve on the inverted HCFC−22 drum and the gauge
set valves. Pump the remaining refrigerant out of the recovery
machine and turn the machine off.
FLUSHING LINE SET AND INDOOR COIL (2 OF 2)
4
TYPICAL CHECK EXPANSION VALVE INSTALLATION PROCEDURE
This outdoor unit is designed for use in systems that use check expansion valve metering device. See the Lennox 13ACX Engineering Handbook
for approved check expansion valve kit match−ups and application information.
TWO PIECE
PATCH PLATE
(UNCASED
COIL ONLY)
DISTRIBUTOR
TUBES
The check expansion valve unit can be installed internal or
external to the indoor coil. In applications where an uncased coil
is being installed in a field−provided plenum, install the check
(Uncased Coil Shown) expansion valve in a manner that will provide access for field
servicing of the check expansion valve. Refer to below
LIQUID LINE STUB
illustration for reference during installation of check expansion
CHECK
END
ORIFICE
EXPANSION valve unit.
HOUSING
VALVE
TEFLON
RING
A.
TEFLON
RING
DISTRIBUTOR
ASSEMBLY
SENSING
LINE
B.
C.
EQUALIZER
LINE
LIQUID LINE
ASSEMBLY WITH
BRASS NUT
D.
E.
MALE EQUALIZER LINE
FITTING (SEE
EQUALIZER LINE
INSTALLATION FOR
FURTHER DETAILS)
VAPOR
LINE
11 12 1
2
10
9
3
4
8
7 6 5
1/2 TURN
Remove the field−provided fitting that temporary reconnected the liquid
line to the indoor unit’s distributor assembly.
Install one of the provided Teflon rings around the stubbed end of the
check expansion valve and lightly lubricate the connector threads and
expose surface of the Teflon ring with refrigerant oil.
Attach the stubbed end of the check expansion valve to the liquid line
orifice housing. Finger tighten and use an appropriately sized wrench to
turn an additional 1/2 turn clockwise as illustrated in the figure above, or
20 ft−lb.
Place the remaining Teflon washer around the other end of the check
expansion valve. Lightly lubricate connector threads and expose surface of the Teflon ring with refrigerant oil.
Attach the liquid line assembly to the check expansion valve. Finger
tighten and use an appropriately sized wrench to turn an additional 1/2
turn clockwise as illustrated in the figure above or 20 ft−lb.
LIQUID LINE
ON LINES SMALLER THAN 7/8",
MOUNT SENSING BULB AT
EITHER THE 3 OR 9 O’CLOCK
POSITION.
VAPOR LINE
SENSING BULB INSULATION IS REQUIRED
IF MOUNTED EXTERNAL TO THE COIL
CASING. SENSING BULB INSTALLATION
FOR BULB POSITIONING.
BULB
12
BULB
SENSING BULB INSTALLATION
A.
NOTE Confirm proper thermal contact between vapor line
and check expansion bulb before insulating the sensing bulb
once installed.
B.
VAPOR LINE
Attach the vapor line sensing bulb in the proper orientation
as illustrated to the right using the clamp and screws provided.
Connect the equalizer line from the
check expansion valve to the
equalizer vapor port on the vapor
line. Finger tighten the flare nut
plus 1/8 turn (7 ft−lbs) as illustrated below.
12
1/8 TURN
11 12 1
2
10
9
3
4
8
5
7
6
BULB
B.
BULB
NOTE NEVER MOUNT ON BOTTOM OF LINE.
FLARE SEAL CAP
EQUALIZER LINE INSTALLATION
A.
ON 7/8" AND LARGER LINES,
MOUNT SENSING BULB AT
EITHER THE 4 OR 8 O’CLOCK
POSITION. NEVER MOUNT ON
BOTTOM OF LINE.
FLARE NUT
OR
Remove and discard either the flare seal cap or flare nut
with copper flare seal bonnet from the equalizer line port
on the vapor line as illustrated in the figure to the right.
Remove and discard either the flare seal cap or flare nut
with copper flare seal bonnet from the equalizer line port on
the vapor line as illustrated in the figure to the right.
COPPER FLARE
SEAL BONNET
MALE BRASS EQUALIZER
LINE FITTING
VAPOR LINE
Page 11
13ACX SERIES
Leak Testing the System
LEAK TEST
LINE SET AND INDOOR COIL
1
CONNECT GAUGE SET
A.
B.
NOTE Normally, the high pressure hose is connected to the liquid line port. However, connecting it to the vapor port better protects the manifold gauge set from high
pressure damage.
Connect an HFC−410A manifold gauge set high
pressure hose to the vapor valve service port.
With both manifold valves closed, connect the
cylinder of HFC−410A refrigerant to the center port
of the manifold gauge set.
LOW
HIGH
MANIFOLD GAUGE SET
NOTE Later in the procedure, the HFC−410A
container will be replaced by the nitrogen container.
OUTDOOR UNIT
A
B
USE REGULATOR TO FLOW
NITROGEN AT 1 TO 2 PSIG.
TO VAPOR
SERVICE VALVE
NITROGEN
2
TEST FOR LEAKS
HFC−410A
After the line set has been connected to the indoor unit and air conditioner, check the line set connections and
indoor unit for leaks. Use the following procedure to test for leaks:
A. With both manifold valves closed, connect the cylinder of HFC−410A refrigerant to the center port of the manifold gauge set. Open
the valve on the HFC−410A cylinder (vapor only).
B.
Open the high pressure side of the manifold to allow HFC−410A into the line set and indoor unit. Weigh in a trace amount of
HFC−410A. [A trace amount is a maximum of two ounces (57 g) refrigerant or three pounds (31 kPa) pressure]. Close the valve on
the HFC−410A cylinder and the valve on the high pressure side of the manifold gauge set. Disconnect the HFC−410A cylinder.
C.
Connect a cylinder of dry nitrogen with a pressure regulating valve to the center port of the manifold gauge set.
D.
Adjust dry nitrogen pressure to 150 psig (1034 kPa). Open the valve on the high side of the manifold gauge set in order to pressurize the
line set and the indoor unit.
E.
After a few minutes, open one of the service valve ports and verify that the refrigerant added to the system earlier is measurable
with a leak detector.
F.
After leak testing disconnect gauges from service ports.
WARNING
WARNING
When using a high pressure gas such as
dry nitrogen to pressurize a refrigeration
or air conditioning system, use a
regulator that can control the pressure
down to 1 or 2 psig (6.9 to 13.8 kPa).
Fire, Explosion and Personal Safety
Hazard.
Failure to follow this warning could
result in damage, personal injury or
death.
Never use oxygen to pressurize or
purge refrigeration lines. Oxygen,
when exposed to a spark or open
flame, can cause damage by fire
and/or an explosion, that could result
in personal injury or death.
WARNING
Refrigerant can be harmful if it is inhaled. Refrigerant
must be used and recovered responsibly.
Failure to follow this warning may result in personal injury
or death.
IMPORTANT
Leak detector must be capable of sensing HFC
refrigerant.
Page 12
506374−01 07/10
Evacuating the System
EVACUATING
1
MANIFOLD
GAUGE SET
LINE SET AND INDOOR COIL
CONNECT GAUGE SET
A.
B.
C.
D.
Connect low side of manifold gauge
set with 1/4 SAE in−line tee to vapor line
service valve
Connect high side of manifold gauge
set to liquid line service valve
Connect micron gauge available
connector on the 1/4 SAE in−line tee.
Connect the vacuum pump (with
vacuum gauge) to the center port of the
manifold gauge set. The center port line
will be used later for both the HFC−410A
and nitrogen containers.
A
HIGH
LOW
NOTE Remove cores from service valves (if not already done).
A34000 1/4 SAE TEE WITH
SWIVEL COUPLER
500
OUTDOOR
UNIT
MICRON
GAUGE
C
TO VAPOR
SERVICE VALVE
USE REGULATOR TO FLOW
NITROGEN AT 1 TO 2 PSIG.
HFC−410A
B
TO LIQUID LINE
SERVICE VALVE
VACUUM PUMP
D
RECOMMEND
MINIMUM 3/8" HOSE
NITROGEN
2
EVACUATE THE SYSTEM
A.
Open both manifold valves and start the vacuum pump.
B.
Evacuate the line set and indoor unit to an absolute pressure of 23,000 microns (29.01 inches of mercury).
NOTE During the early stages of evacuation, it is desirable to close the manifold gauge valve at least once. A rapid rise in pressure
indicates a relatively large leak. If this occurs, repeat the leak testing procedure.
NOTE The term absolute pressure means the total actual pressure within a given volume or system, above the absolute zero of
pressure. Absolute pressure in a vacuum is equal to atmospheric pressure minus vacuum pressure.
C.
When the absolute pressure reaches 23,000 microns (29.01 inches of mercury), close the manifold gauge valves, turn off the vacuum
pump and disconnect the manifold gauge center port hose from vacuum pump. Attach the manifold center port hose to a dry nitrogen
cylinder with pressure regulator set to 150 psig (1034 kPa) and purge the hose. Open the manifold gauge valves to break the vacuum in
the line set and indoor unit. Close the manifold gauge valves.
D.
Shut off the dry nitrogen cylinder and remove the manifold gauge hose from the cylinder. Open the manifold gauge valves to release the
dry nitrogen from the line set and indoor unit.
E.
Reconnect the manifold gauge to the vacuum pump, turn the pump on, and continue to evacuate the line set and indoor unit until the
absolute pressure does not rise above 500 microns (29.9 inches of mercury) within a 20−minute period after shutting off the vacuum pump
and closing the manifold gauge valves.
F.
When the absolute pressure requirement above has been met, disconnect the manifold hose from the vacuum pump and connect it to
an upright cylinder of HFC−410A refrigerant. Open the manifold gauge valve 1 to 2 psig in order to release the vacuum in the line set and
indoor unit.
G.
Perform the following:
1/6 TURN
Close manifold gauge valves.
Shut off HFC−410A cylinder.
Reinstall service valve cores by removing manifold hose from service valve. Quickly install cores with
core tool while maintaining a positive system pressure.
Replace the stem caps and secure finger tight, then tighten an additional one−sixth (1/6) of a turn as
illustrated.
11 12 1
2
10
9
3
4
8
7 6 5
Page 13
13ACX SERIES
IMPORTANT
Use a thermocouple or thermistor electronic vacuum
gauge that is calibrated in microns. Use an instrument
capable of accurately measuring down to 50 microns.
WARNING
Danger of Equipment Damage. Avoid deep vacuum
operation. Do not use compressors to evacuate a
system. Extremely low vacuums can cause internal
arcing and compressor failure. Damage caused by
deep vacuum operation will void warranty.
Evacuating the system of non−condensables is critical for
proper operation of the unit. Non−condensables are
defined as any gas that will not condense under
temperatures and pressures present during operation of
an air conditioning system. Non−condensables and water
suction combine with refrigerant to produce substances
that corrode copper piping and compressor parts.
Electrical
In the U.S.A., wiring must conform with current local codes
and the current National Electric Code (NEC). In Canada,
wiring must conform with current local codes and the current
Canadian Electrical Code (CEC).
Refer to the furnace or air handler installation instructions
for additional wiring application diagrams and refer to unit
nameplate for minimum circuit ampacity and maximum
overcurrent protection size.
24VAC TRANSFORMER
Use the transformer provided with the furnace or air
handler for low-voltage control power (24VAC − 40 VA
minimum)
INSTALL THERMOSTAT
SIZE CIRCUIT AND INSTALL SERVICE
DISCONNECT SWITCH
Refer to the unit nameplate for minimum circuit ampacity, and maximum
fuse or circuit breaker (HACR per NEC). Install power wiring and properly
sized disconnect switch.
Install room thermostat (ordered separately) on an inside wall
approximately in the center of the conditioned area and 5 feet (1.5m) from
the floor. It should not be installed on an outside wall or where it can be
affected by sunlight or drafts.
MAIN FUSE BOX/
BREAKER PANEL
THERMOSTAT
SERVICE
DISCONNECT
SWITCH
5 FEET
(1.5M)
NOTE Units are approved for use only with copper conductors.
Ground unit at disconnect switch or to an earth ground.
NOTE 24VAC, Class II circuit connections are made in the control
panel.
WARNING
Electric Shock Hazard. Can cause injury or death. Unit must be grounded in accordance with national and
local codes.
Line voltage is present at all components when unit is not in operation on units with single-pole contactors.
Disconnect all remote electric power supplies before opening access panel. Unit may have multiple power
supplies.
Page 14
506374−01 07/10
ROUTING HIGH VOLTAGE/ GROUND AND CONTROL WIRING
HIGH VOLTAGE / GROUND WIRES
Any excess high voltage field wiring should be trimmed and
secured away from any low voltage field wiring. To facilitate a
conduit, a cutout is located in the bottom of the control panel.
Connect conduit to the control panel using a proper conduit fitting.
SINGLE PHASE
HIGH VOLTAGE
CONNECTIONS
(CONTACTOR)
B
CONTROL
WIRING
CONTROL WIRING
GROUND
NOTE Wire tie provides low voltage control wire strain relief and to
maintain separation of field installed low and high voltage circuits.
HIGH VOLTAGE
FIELD WIRING
NOTE For proper voltages, select thermostat wire (control wires)
gauge per Table above.
LOW VOLTAGE
FIELD WIRING
FACTORY
WIRING
NOTE Do not bundle any excess 24VAC control wires inside
control panel.
Install low voltage wiring from outdoor to indoor unit and from thermostat
to indoor unit as illustrated.
A. Run 24VAC control wires through hole with grommet and secure with
provided wire tie.
B.
Make 24VAC thermostat wire connections. Locate the two wires from the
contactor and make connection using field provided wire nuts:
HIGH VOLTAGE
FLEXIBLE CONDUIT
THERMOSTAT
INDOOR UNIT
POWER
R
R
HEAT
W
W1
Yellow to Y1
Black to C (common)
COOLING
Y
Y
WIRE RUN LENGTH
AWG# INSULATION TYPE
LESS THAN 100’ (30 METERS)
18
MORE THAN 100’ (30 METERS) 16
A
GROMMET
AND WIRE TIE
G
INDOOR
BLOWER
OUTDOOR
UNIT
Y1
G
TEMPERATURE RATING
COMMON
35ºC MINIMUM.
C
C
C
Figure 8. Typical 13ACX Unit Wiring Diagram
Page 15
13ACX SERIES
GAUGE SET
MANIFOLD GAUGE SET
CONNECTIONS FOR TESTING AND CHARGING
HIGH
LOW
LINE
B SUCTION
SERVICE PORT
CONNECTION
OUTDOOR UNIT
REFRIGERANT TANK
CHARGE IN
LIQUID PHASE
A
DIGITAL SCALE
D
TEMPERATURE
SENSOR
C
TO LIQUID
LINE SERVICE
VALVE
TEMPERATURE SENSOR
(LIQUID LINE)
A.
Close manifold gauge set valves and connect the center hose to a cylinder of HFC−410A. Set for liquid phase charging.
B.
Connect the manifold gauge set’s low pressure side to the suction line service port.
C.
Connect the manifold gauge set’s high pressure side to the liquid line service port.
D.
Position temperature sensor on liquid line near liquid line service port.
Figure 9. Gauge Set Setup and Connections
2. Inspect all factory− and field−installed wiring for loose
connections.
Servicing Units Delivered Void of Charge
If the outdoor unit is void of refrigerant, clean the system
using the procedure described below.
1. Leak check system using procedure outlined on Page
12.
2. Evacuate the system using procedure outlined on
Page 13.
3. Use nitrogen to break the vacuum and install a new
filter drier in the system.
4. Evacuate the system again using procedure outlined
on Page 13.
5. Weigh in refrigerant using procedure outlined under
Start−Up and Charging Procedures.
6. Monitor the system to determine the amount of
moisture remaining in the oil. It may be necessary to
replace the filter drier several times to achieve the
required dryness level. If system dryness is not
verified, the compressor will fail in the future.
3. After evacuation is complete, open the liquid line and
suction line service valves to release the refrigerant
charge (contained in air conditioner) into the system.
4. Replace the stem caps and tighten to the value listed
in Table 1.
5. Check voltage supply at the disconnect switch. The
voltage must be within the range listed on the unit’s
nameplate. If not, do not start the equipment until you
have consulted with the power company and the
voltage condition has been corrected.
6. Set the thermostat for a cooling demand. Turn on
power to the indoor handler and close the air
conditioner disconnect switch to start the unit.
7. Recheck voltage while the unit is running. Power must
be within range shown on the nameplate.
8. Check system for sufficient refrigerate using the
procedures that follow.
Unit Start−Up
System Refrigerant
IMPORTANT
If unit is equipped with a crankcase heater, it should be
energized 24 hours before unit start−up to prevent
compressor damage as a result of slugging.
This section outlines procedures for:
1. Rotate fan to check for binding.
Page 16
506374−01 07/10
1. Connecting gauge set for testing and charging;
2. Checking and adjusting indoor airflow;
3. Adding or removing refrigerant.
ADDING OR REMOVING REFRIGERANT
This system uses HFC−410A refrigerant which operates at much higher pressures than HCFC−22. The pre−installed liquid
line filter drier is approved for use with HFC−410A only. Do not replace it with components designed for use with HCFC−22.
This unit is NOT approved for use with coils which use capillary tubes or fixed orifices as a refrigerant metering device.
Check airflow using the Delta−T (DT) process using the illustration in Figure 10.
AIRFLOW
INDOOR COIL
Dry−bulb
DT
80 24 24 24 23 23 22 22 22 20 19 18 17 16 15
Temperature of air
entering indoor
78 23 23 23 22 22 21 21 20 19 18 17 16 15 14
coil ºF
76 22 22 22 21 21 20 19 19 18 17 16 15 14 13
74 21 21 21 20 19 19 18 17 16 16 15 14 13 12
72 20 20 19 18 17 17 16 15 15 14 13 12 11 10
A
70 19 19 18 18 17 17 16 15 15 14 13 12 11 10
Wet−bulb ºF 57 58 59 60 61 62 63 64 65 66 67 68 69 70
B
DRY
BULB
A
72º
TDrop
C
53º
19º
air flow
air flow
B
64º
DRY BULB
INDOOR COIL
All temperatures are expressed in ºF
WET BULB
Use the following procedure to adjust for optimal air flow across the indoor coil:
1. Determine the desired DT Measure entering air temperature using dry bulb (A) and wet bulb (B). DT
is the intersecting value of A and B in the Table (see triangle).
2. Find temperature drop across coil Measure the coil’s dry bulb entering and leaving air temperatures
(A and C). Temperature Drop Formula: (TDrop) = A minus C.
3. Determine if fan needs adjustment If the difference between the measured TDrop and the desired
DT (TDrop–DT) is within +3º, no adjustment is needed. See example below:
Assume DT = 15 and A temp. = 72º, these C temperatures would necessitate stated actions:
Cº
TDrop –
DT
=
ºF ACTION
Changing air flow affects all temperatures; recheck
19 –
15 = 4 Increase the airflow
temperatures to confirm that the temperature drop
58º
14 –
15 = −1 (within +3º range) no change
and DT are within +3º.
62º
10 –
15 = −5 Decrease the airflow
4. Adjust the fan speed See indoor unit instructions to increase/decrease fan speed.
53º
Figure 10. Checking Indoor Airflow over Evaporator Coil using Delta−T (DT) Chart
Page 17
13ACX SERIES
START: Determine how refrigerant is metered
WHEN TO CHARGE?
TXV
Warm weather best
RFC
Which
metering
device?
Can charge in colder weather
CHARGE METHOD? Determine by:
Metering device type
Outdoor ambient temperature
REQUIREMENTS:
Sufficient heat load in structure
Indoor temperature between 70-80ºF
(21−26ºC)
Manifold gauge set connected to unit
Thermometers:
− to measure outdoor ambient
temperature
− to measure liquid line temperature
− to measure suction line
temperature
65ºF
(18.3ºC) and
Above
APPROACH OR
SUBCOOLING
64ºF
(17.7ºC) and
Below
40ºF
(4.4ºC) and
Above
39ºF
(3.8ºC) and
Below
WEIGH-IN
SUPERHEAT
WEIGH-IN
Figure 11. Determining Charge Method
START: Measure outdoor ambient temperature
USE EITHER APPROACH
OR SUBCOOLING
METHOD
65ºF
(18.3ºC) and
Above
64ºF
(17.7ºC) and
Below
ABOVE or
BELOW
1. Check Liquid and suction line pressures
2. Compare unit pressures with Table 3,
Normal Operating Pressures.
3. Conduct leak check; evacuate as
previously outlined.
4. Weigh in the unit nameplate charge plus
any charge required for line set differences
over feet.
WEIGH IN TXV
Refrigerant Charge per Line Set Length
Liquid Line
Set Diameter
Ounces per 5 feet (g per 1.5 m)
adjust from 15 feet (4.6 m) line set*
3/8" (9.5 mm)
3 ounce per 5’ (85 g per 1.5 m)
This nameplate is for illustration
purposes only. Go to actual
nameplate on outdoor unit for
charge information.
NOTE − *If line length is greater than 15 ft. (4.6 m), add this
amount. If line length is less than 15 ft. (4.6 m), subtract this
amount.
Figure 12. HFC−410A Weigh In TXV Method
Page 18
506374−01 07/10
START: Measure outdoor ambient temperature
65ºF
(18.3ºC) and
Above
USE
DO NOT
WEIGH-IN
CHARGE
METHOD
UNIT
Weigh-in
(Resultsorofremove
charging
refrigerat low
ant
temperatures
based upon not
linereliable)
length
ABOVE or
BELOW
64ºF
(17.7ºC) and
Below
1. Confirm proper airflow across coil using Figure
10.
2. Compare unit pressures with Table 3, Normal
Operating Pressures.
3. Set thermostat to call for heat (must have a
cooling load between 70-80ºF (21−26ºC).
4. Connect gauge set.
5. When heat demand is satisfied, set thermostat
to call for cooling.
6. Allow temperatures and pressures to stabilize.
7. Record outdoor ambient temperature:
AMBº =_________
8. Record liquid line temperature:
LIQº = __________
If refrigerant is added
or removed, retest to
confirm that unit is
properly charged.
9. Subtract to determine approach (APPº):
LIQº_____ − AMBº _____ = APPº_____
10. Compare results with table below.
APPº (Approach) Values(F:+/−1.0° [C: +/−0.6°])
If value is greater than shown (high approach),
add refrigerant; if less than shown (liquid
temperature too close to ambient temperature,
low approach), remove refrigerant.
ºF (ºC)*
−018
−024
−030
−036
Any
4 (2.2)
8 (4.4) 8 (4.4) 11 (6.1)
*Temperature of air entering outdoor coil
−042
9 (5.0)
−048
8 (4.4)
−060
9 (5.0)
Figure 13. HFC−410A Approach TXV Charge
START: Measure outdoor ambient temperature
USE
METHOD
DO WEIGH-IN
NOT CHARGE
UNIT
Weigh-in
or of
remove
refrigerant
(Results
charging
at low
based
upon line length
temperatures
not reliable)
CARDBOARD OR
PLASTIC SHEET
If refrigerant is added
or removed, verify
charge using the
Approach Method.
64ºF
(17.7ºC) and
Below
65ºF
(18.3ºC) and
Above
ABOVE or
BELOW
BLOCK OUTDOOR COIL: [sometimes necessary
with lower temperatures] Use cardboard or plastic
sheet to restrict the airflow through the outdoor coil
to achieve pressures from 325−375 psig
(2240−2585 kPa). Higher pressures are needed to
check charge. Block equal sections of air intake
panels and move coverings sideways until the
liquid pressure is in the above noted ranges.
1. Confirm proper airflow across coil using Figure
10.
2. Compare unit pressures with Table 3, Normal
Operating Pressures.
3. Set thermostat to call for heat (must have a
cooling load between 70-80ºF (21−26ºC)
4. Connect gauge set
5. Measure outdoor ambient temperature
6. When heat demand is satisfied, set thermostat to
call for cooling
7. Allow temperatures and pressures to stabilize.
NOTE − If necessary, block outdoor coil to
maintain 325 − 375 psig.
8. Record liquid line temperature:
LIQº = ______
9. Measure liquid line pressure and use the value to
determine saturation temperature (see Table 4):
SATº = ______
If value is MORE
than shown, remove
refrigerant.
10. Subtract to determine subcooling (SCº):
SATº_____ − LIQº _____ = SCº _____
11. Compare results with table below.
SCº (Subcooling) Values (F:+/−1.0° [C: +/−0.6°])
If value is LESS
than shown, add
refrigerant.
MORE or
LESS
ºF (ºC)*
−018
−024
−030
−036
Any
10 (5.6) 10 (5.6) 9 (5.0) 12 (6.7)
*Temperature of air entering outdoor coil
−042
9 (5.0)
−048
9 (5.0)
−060
7 (3.9)
Figure 14. HFC−410A Subcooling TXV Charge
Page 19
13ACX SERIES
START: Measure outdoor ambient temperature
USE SUPERHEAT
40ºF
(4.4ºC) and
Above
1. Check Liquid and suction line pressures
2. Compare unit pressures with Table 3,
Normal Operating Pressures.
3. Conduct leak check; evacuate as
previously outlined.
4. Weigh in the unit nameplate charge plus
any charge required for line set differences
over feet.
39ºF
(3.8ºC) and
Below
ABOVE or
BELOW
WEIGH IN RFC
Refrigerant Charge per Line Set Length
Liquid Line
Set Diameter
Ounces per 5 feet (g per 1.5 m)
adjust from 15 feet (4.6 m) line set*
3/8" (9.5 mm)
3 ounce per 5’ (85 g per 1.5 m)
This nameplate is for illustration purposes
only. Go to actual nameplate on outdoor unit
for charge information.
NOTE − *If line length is greater than 15 ft. (4.6 m), add this
amount. If line length is less than 15 ft. (4.6 m), subtract this
amount.
Figure 15. HFC−410A Weigh In RFC Method
START: Measure outdoor ambient temperature
USE WEIGH-IN METHOD
Weigh-in or remove refrigerant
based upon line length
39ºF
(3.8ºC) and
Below
1. Confirm proper airflow across coil using Figure
10.
2. Compare unit pressures with Table 3, Normal
Operating Pressures.
3. Use SUPERHEAT to correctly charge unit or to
verify
the charge
is correct.
4. Set
thermostat
to call
for heat (must have a cooling
load between 70-80ºF (21−26ºC)
5. Connect gauge set.
6. When heat demand is satisfied, set thermostat to
call for cooling.
7. Allow temperatures and pressures to stabilize.
8. Measure the suction line pressure and use the use
value to determine saturation temperature (Table
4):
SATº =_________
40ºF
(4.4ºC) and
Above
ABOVE or
BELOW
SHº (Superheat) Values (+/−5ºF)
If
refrigerant
is
REMOVED, retest to
confirm that unit is
properly charged.
Wet Bulb (air entering indoor coil)
ºF* 50 52 54 56 58 60 62 64 66 68 70 72 74 76
40 15 18 20 23 26 29 32 34 38 41 43 46 48 51
45 13 16 18 21 24 27 30 33 36 39 41 44 46 49
50
11 14 16 19 22 25 28 31 34 37 39 42 44 47
55
9 12 14 17 20 23 27 30 33 36 38 40 42 44
60
7 10 12 15 18 21 24 27 30 33 35 38 40 43
65
- 6 10 13 16 19 21 24 27 30 33 36 38 41
70
- - 7 10 13 16 19 21 24 27 30 33 36 39
75
- - - 6 9 12 15 18 21 24 28 31 34 37
80
- - - - 5 8 12 15 18 21 25 28 31 35
85
- - - - - - 8 11 15 19 22 26 30 33
90
- - - - - - 5 9 13 16 20 24 27 31
95
- - - - - - - 6 10 14 18 22 25 29
100 - - - - - - - - 8 12 16 21 24 28
105 - - - - - - - - 5 9 13 17 22 26
110 - - - - - - - - - 6 11 15 20 25
115 - - - - - - - - - - 8 14 18 24
* Dry−bulb temperature (ºF) of entering outdoor ambient air.
If value is LESS than
shown, then REMOVE
refrigerant.
MORE or
LESS
9. Record suction line temperature:
VAPº =_________
10. Subtract to determine superheat (SHº):
VAPº − _____ SATº ______ = SHº______
11. Record the wet bulb temperature (air entering
indoor coil):
WB =_______
12. Record outdoor ambient temperature.
13. Compare results with table to the left.
NOTE − Do not attempt to charge system where a
dash appears, system could be overcharged.
Superheat is taken at suction line service port.
Suction line superheat must never be less than 5ºF
at the suction line service port.
If value is MORE
than shown, then
ADD refrigerant.
Figure 16. HFC−410A Superheat RFC Method
Page 20
506374−01 07/10
If refrigerant is
ADDED, retest to
confirm that unit is
properly charged.
Table 3. HFC−410A Normal Operating Pressures (Liquid +10 and Suction +5 psig)
Use this table to perform maintenance checks; it is not a procedure for charging the
system. Minor variations in these pressures may be due to differences in installations.
Significant deviations could mean that the system is not properly charged or that a
problem exists with some component in the system.
IMPORTANT
13ACX
−018
5F (5C)*
Liquid / Suction
Expansion Valve (TXV)
−024
−030
−036
−042
−048
−060
Liquid / Suction
Liquid / Suction
Liquid / Suction
Liquid / Suction
Liquid / Suction
Liquid / Suction
65 (18)
233 / 132
244 / 137
248 / 127
263 / 135
238 /132
235 / 132
241 / 130
70 (21)
251 / 133
263 / 138
263 / 131
281 / 138
262 / 133
254 / 132
260 / 130
75 (24)
265 / 133
285 / 139
284 / 132
302 / 140
280 / 134
276 / 134
280 / 132
80 (27)
292 / 135
307 / 140
307 / 134
325 / 142
301 / 136
298 / 134
299 / 134
85 (29)
314 / 136
329 / 141
330 / 135
349 / 142
327 / 137
323 / 135
321 / 135
90 (32)
338 / 137
354 / 142
355 / 136
375 / 143
353 / 138
350 / 137
344 / 134
95 (35)
362 / 138
379 / 143
380 / 137
404 / 144
377 / 140
377 / 138
371 / 135
100 (38)
388 / 140
404 / 144
407 / 138
433 / 145
404 / 141
406 / 140
400 / 137
105 (41)
415 / 141
438 / 145
434 / 139
462 / 147
435 / 142
430 / 141
428 / 139
110 (43)
444 / 142
464 / 147
465 / 141
494 / 149
465 / 143
464 / 142
458 / 141
115 (45)
475 / 143
495 / 148
497 / 142
527 / 150
499 / 144
495 / 143
484 / 142
Fixed Orifice (RFC)
65 (18)
233 / 121
246 / 126
245 / 123
261 / 134
246 / 126
247 / 125
248 / 124
70 (21)
250 / 124
265 / 129
265 / 126
281 / 136
263 / 128
266 / 128
266 / 126
75 (24)
270 / 128
286 / 132
286 / 129
301 / 138
284 / 131
286 / 131
288 / 130
80 (27)
291 / 131
307 /135
308 / 132
324 / 140
305 / 133
307 / 133
309 / 133
85 (29)
313 / 134
330 / 137
331 / 135
346 / 142
327 / 135
329 / 135
330 / 135
90 (32)
335 / 136
353 / 140
355 / 138
371 / 144
350 / 138
353 / 138
354 / 138
95 (35)
359 / 138
378 / 142
380 / 140
396 / 146
374 / 140
377 / 140
377 / 140
100 (38)
383 / 140
402 / 143
405 / 142
422 / 148
399 / 142
403 / 142
406 / 142
105 (41)
409 / 142
428 / 145
431 / 144
448 / 150
424 / 144
428 / 144
431 / 144
110 (43)
436 / 145
456 / 147
458 / 146
477 / 151
452 / 146
455 / 146
457 / 146
115 (46)
464 / 147
486 / 149
487 / 148
506 / 153
481 / 148
483 / 147
484 / 148
*Values shown are typical pressures; indoor unit match up, indoor air quality equipment, and indoor load will cause the pressures to vary.
**Temperature of the air entering the outside coil.
Table 4. HFC−410A Temperature Pressure (Psig)
°F
°C
Psig
°F
°C
Psig
−40
−35
−30
−25
−20
−15
−10
−5
0
5
10
15
20
25
30
35
40
45
50
55
−40.0
−37.2
−34.4
−31.7
−28.9
−26.1
−23.3
−20.6
−17.8
−15.0
−12.2
−9.4
−6.7
−3.9
−1.1
1.7
4.4
7.2
10.0
12.8
11.6
14.9
18.5
22.5
26.9
31.7
36.8
42.5
48.6
55.2
62.3
70.0
78.3
87.3
96.8
107
118
130
142
155
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
135
140
145
150
15.6
18.3
21.1
23.9
26.7
29.4
32.2
35.0
37.8
40.6
43.3
46.1
48.9
51.7
54.4
57.2
60.0
62.8
65.6
170
185
201
217
235
254
274
295
317
340
365
391
418
446
476
507
539
573
608
Page 21
13ACX SERIES
Removing and Installing Louvers
WARNING
To prevent personal injury, or damage to panels, unit or structure, be sure to observe the following:
While installing or servicing this unit, carefully stow all removed panels out of the way, so that the panels will not cause injury to personnel,
nor cause damage to objects or structures nearby, nor will the panels be subjected to damage (e.g., being bent or scratched).
While handling or stowing the panels, consider any weather conditions, especially windy conditions, that may cause panels to be blown
around and battered.
PANEL B
PANEL C
ORDER OF REMOVAL AND REINSTALLATION
When removing the unit panels. Remove panel A
first, then B, C and finally D. When reinstalling panels, reverse that order starting with panel D, C, B
and finally A.
WARNING
PANEL A
PANEL D
REMOVAL
INSTALLATION
TOP CAP
STEP 1
TO REMOVE PANEL,
REMOVE MOUNTING
SCREWS SECURING
PANEL TO THE UNIT.
STEP 1
STARTING WITH PANEL D,
INSERT PANEL UNDER UNIT
TOP CAP LIP AND LIFT
SLIGHTLY TO CLEAR SIDE LIP
OF PANEL FROM BASE.
SIDE
GROOVE
PANEL A
STEP 2
STEP 2
SLIGHTLY LIFT PANEL A IN
ORDER TO CLEAR SIDE
LIPS OF PANEL FROM
BASE OF UNIT.
MOVE PANEL IN TOWARDS UNIT.
ALIGN LEFT/RIGHT SIDE LIPS OF
PANEL WITH GROOVE INSERTS
ALONG LEFT/RIGHT SIDE OF UNIT.
STEP 3
TILT PANEL OUT SLIGHTLY
AND PULL DOWNWARD
TO REMOVE.
REPEAT STEPS 1, 2 AND
3 TO REMOVE PANELS B,
C AND FINALLY D.
STEP 3
SECURE PANEL, WITH
MOUNTING SCREWS.
REPEAT STEPS 1 AND 2 TO INSTALL PANELS C,
B AND FINALLY A.
PANEL A
Page 22
506374−01 07/10
BASE
PANEL D
6. Inspect drain holes in coil compartment base and
clean if necessary.
System Operation
NOTE - If insufficient cooling occurs, the unit should be
gauged and refrigerant charge should be checked.
IMPORTANT
Some scroll compressor have internal vacuum protector
that will unload scrolls when suction pressure goes
below 20 psig. A hissing sound will be heard when the
compressor is running unloaded. Protector will reset
when low pressure in system is raised above 40 psig. DO
NOT REPLACE COMPRESSOR.
The outdoor unit and indoor blower will cycle on and off as
dictated by demands from the room thermostat. When the
thermostat’s blower switch is in the ON position, the indoor
blower will operate continuously.
HIGH PRESSURE SWITCH
13ACX units are equipped with a high-pressure switch that
is located in the liquid line of the compressor as illustrated
in figure on page 2.
The switch is a Single Pole, Single Throw (SPST),
manual−reset switch which is normally closed and
removes power from the compressor when discharge
pressure rises above factory setting at 590 + 10 psi. The
manual−reset switch can be identified by a red cap that is
press to preform the reset function.
Maintenance
DEALER
WARNING
Electric shock hazard. Can cause injury
or death. Before attempting to perform
any service or maintenance, turn the
electrical power to unit OFF at disconnect
switch(es). Unit may have multiple power
supplies.
WARNING
Improper installation, adjustment, alteration, service or
maintenance can cause personal injury, loss of life, or
damage to property.
Installation and service must be performed by a licensed
professional installer (or equivalent) or a service agency.
Maintenance and service must be performed by a qualified
installer or service agency. At the beginning of each
cooling season, the system should be checked as follows:
Outdoor Coil
Clean and inspect outdoor coil (may be flushed with a
water hose). Ensure power is off before cleaning.
NOTE It may be necessary to flush the outdoor coil
more frequently if it is exposed to substances which are
corrosive or which block airflow across the coil (e.g., pet
urine, cottonwood seeds, fertilizers, fluids that may contain
high levels of corrosive chemicals such as salts)
Sea Coast Moist air in ocean locations can carry salt,
which is corrosive to most metal. Units that are located
near the ocean require frequent inspections and
maintenance. These inspections will determine the
necessary need to wash the unit including the outdoor coil.
Consult your installing contractor for proper
intervals/procedures for your geographic area or service
contract.
Indoor Unit
1. Clean or change filters.
2. Lennox blower motors are prelubricated and
permanently sealed. No more lubrication is needed.
3. Adjust blower speed for cooling. Measure the pressure
drop over the coil to determine the correct blower CFM.
Refer to the unit information service manual for pressure
drop tables and procedure.
4. Belt Drive Blowers − Check belt for wear and proper
tension.
5. Check all wiring for loose connections.
6. Check for correct voltage at unit. (blower operating)
7. Check amp draw on blower motor.
Motor Nameplate:_________ Actual:__________.
Indoor Coil
1. Clean coil if necessary.
2. Check connecting lines, joints and coil for evidence of
oil leaks.
3. Check condensate line and clean if necessary.
HOMEOWNER
Cleaning of the outdoor unit’s coil should be performed by
a trained service technician. Contact your dealer and set
up a schedule (preferably twice a year, but at least once a
year) to inspect and service your outdoor unit. The
following maintenance may be performed by the
homeowner.
Outdoor Unit
1. Outdoor unit fan motor is pre−lubricated and sealed.
No further lubrication is needed.
2. Visually inspect all connecting lines, joints and coils for
evidence of oil leaks.
3. Check all wiring for loose connections.
4. Check for correct voltage at unit (unit operating).
5. Check amp draw on outdoor fan motor.
Motor Nameplate:_________ Actual:__________.
IMPORTANT
Sprinklers and soaker hoses should not be installed
where they could cause prolonged exposure to the
outdoor unit by treated water. Prolonged exposure of the
unit to treated water (i.e., sprinkler systems, soakers,
waste water, etc.) will corrode the surface of steel and
aluminum parts and diminish performance and longevity
of the unit.
Page 23
13ACX SERIES
Outdoor Coil
The outdoor unit must be properly maintained to ensure its
proper operation.
Please contact your dealer to schedule proper
inspection and maintenance for your equipment.
Make sure no obstructions restrict airflow to the
outdoor unit.
Grass clippings, leaves, or shrubs crowding the unit
can cause the unit to work harder and use more
energy.
Keep shrubbery trimmed away from the unit and
periodically check for debris which collects around the
unit.
NOTE The filter and all access panels must be in place
any time the unit is in operation.
4. Electronic Air Cleaner Some systems are
equipped with an electronic air cleaner, designed to
remove airborne particles from the air passing through
the cleaner. If your system is so equipped, ask your
dealer for maintenance instructions.
5. Indoor Unit The indoor unit’s evaporator coil is
equipped with a drain pan to collect condensate
formed as your system removes humidity from the
inside air. Have your dealer show you the location of
the drain line and how to check for obstructions. (This
would also apply to an auxiliary drain, if installed.)
Thermostat Operation
Routine Maintenance
See the ComfortSense® 7000 thermostat homeowner
manual for instructions on how to operate your thermostat.
In order to ensure peak performance, your system must be
properly maintained. Clogged filters and blocked airflow
prevent your unit from operating at its most efficient level.
1. Air Filter Ask your Lennox dealer to show you
where your indoor unit’s filter is located. It will be either
at the indoor unit (installed internal or external to the
cabinet) or behind a return air grille in the wall or
ceiling. Check the filter monthly and clean or replace
it as needed.
2. Disposable Filter Disposable filters should be
replaced with a filter of the same type and size.
If your system fails to operate, check the following before
calling for service:
Verify room thermostat settings are correct.
Verify that all electrical disconnect switches are ON.
Check for any blown fuses or tripped circuit breakers.
Verify unit access panels are in place.
Verify air filter is clean.
If service is needed, locate and write down the unit
model number and have it handy before calling.
NOTE If you are unsure about the filter required for your
system, call your Lennox dealer for assistance.
3. Reusable Filter Many indoor units are equipped
with reusable foam filters. Clean foam filters with a
mild soap and water solution; rinse thoroughly; allow
filter to dry completely before returning it to the unit or
grille.
Preservice Check
Accessories
For update−to−date information, see any of the following
publications:
Lennox 13ACX Engineering Handbook
Lennox Product Catalog
Lennox Price Book
Start−Up and Performance Checklist
Job Name
Job no.
Date
Job Location
City
State
Installer
City
State
Unit Model No.
Serial No.
Service Technician
Nameplate Voltage
Rated Load Ampacity
Compressor
Outdoor Fan
Maximum Fuse or Circuit Breaker
Electrical Connections Tight? Indoor Filter clean? Supply Voltage (Unit Off)
Indoor Blower RPM
S.P. Drop Over Indoor (Dry)
Outdoor Coil Entering Air Temp.
Discharge Pressure
Suction Pressure
Refrigerant Charge Checked?
Outdoor Fan Checked?
Refrigerant Lines:
Leak Checked? Properly Insulated? Service Valves:
Fully Opened?
Caps Tight?
Thermostat
Calibrated? Properly Set? Level? Voltage With Compressor Operating
Page 24
506374−01 07/10
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