Carrier Infinity 15 SEER 50XT-A Instruction manual

50XT---A
Infinity® 15 SEER
Single---Packaged Heat Pump System
with Puron® (R---410A) Refrigerant
Single Phase
2---5 Nominal Tons (Sizes 24---60)
Installation Instructions
!
CAUTION
EQUIPMENT OPERATION HAZARD
Failure to follow this caution may result in improper unit
operation.
OAT sensor must be field installed. Follow installation
instructions for proper installation.
!
CAUTION
EQUIPMENT OPERATION HAZARD
Failure to follow this caution may result in improper unit
operation.
This Infinity unit is designed for use with an Infinity User
Interface.
NOTE: Read the entire instruction manual before starting the
installation.
A09032
TABLE OF CONTENTS
PAGE
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . 2
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
RECEIVING AND INSTALLATION . . . . . . . . . . . . . . . . . 2--13
Check Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Identify Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Inspect Shipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Provide Unit Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Roof Curb . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Slab Mount . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Provide Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Rig and Place Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Rigging/Lifting of Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Select and Install Ductwork . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Converting Horizontal Discharge Units to Downflow
(Vertical) Discharge Units . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Provide for Condensate Disposal . . . . . . . . . . . . . . . . . . . . . . 8
Install Electrical Connections . . . . . . . . . . . . . . . . . . . . . . . . . 9
High--Voltage Connections . . . . . . . . . . . . . . . . . . . . . . . . . 9
Routing Power Leads Into Unit . . . . . . . . . . . . . . . . . . . . . . 9
Connecting Ground Lead to Ground Screw . . . . . . . . . . . . 9
Routing Control Power Wires . . . . . . . . . . . . . . . . . . . . . 11
Outdoor Air Temperature Sensor (OAT) . . . . . . . . . . . . . . 11
Accessory Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Special Procedures for 208--v Operation . . . . . . . . . . . . . . 12
PRE--START--UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
START--UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14--20
Unit Start--Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Sequence of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Check for Refrigerant Leaks . . . . . . . . . . . . . . . . . . . . . . . . . 21
Start--Up Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Fig. 1 -- Unit 50XT--A
Checking Cooling and Heating Control Operation . . . . . . 21
Checking and Adjusting Refrigerant Charge . . . . . . . . . . . 21
Refrigerant Charge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
No Charge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Low Charge Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
To Use Cooling Charging Charts . . . . . . . . . . . . . . . . . . . . 21
Indoor Airflow and Airflow Adjustments . . . . . . . . . . . . . 21
Non--Communicating Emergency Cooling/Heating Mode . . 21
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23--25
Air Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Indoor Fan and Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Outdoor Coil, Indoor Coil, and Condensate Drain Pan . . . . . 24
Outdoor Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Electrical Controls and Wiring . . . . . . . . . . . . . . . . . . . . . . . 24
Refrigerant Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Indoor Airflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Metering Devices–TXV & AccuRater® Piston . . . . . . . . . . . 24
Pressure Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Loss--of--Charge Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
High--Pressure Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Copeland Scroll Compressor (Puron® Refrigerant) . . . . . . . . 25
Refrigerant System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Refrigerant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Compressor Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Servicing Systems on Roofs with Synthetic Materials . . . . 25
Liquid--Line Filter Drier . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Puron (R--410A) Refrigerant Charging . . . . . . . . . . . . . . . 25
TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
FINAL CHECKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
CARE AND MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . 27
START--UP CHECKLIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
1
50XT-- A
SAFETY CONSIDERATIONS
INTRODUCTION
Improper installation adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause death, personal injury, or property
damage. Consult a qualified installer, service agency, or your
distributor or branch for information or assistance. The qualified
installer or agency must use factory--authorized kits or accessories
when modifying this product Refer to the individual instructions
packaged with the kits or accessories when installing.
Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Use quenching cloth for brazing operations.
Have a fire extinguisher available. Read these instructions
thoroughly and follow all warnings or cautions included in
literature and attached to the unit. Consult local building codes, the
current editions of the National Electrical Code (NEC) NFPA 70.
In Canada refer to the current editions of the Canadian electrical
Code CSA C22.1.
The 50XT--A packaged heat pump is fully self--contained and
designed for outdoor installation (See Fig. 1). Standard units are
shipped in a horizontal--discharge configuration for installation on
a rooftop, or a cement slab (see Fig. 4 for roof curb details).
Standard units can be converted to downflow (vertical) discharge
configurations for rooftop applications.
.
Recognize safety information. This is the safety--alert symbol
When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury. Understand
these signal words; DANGER, WARNING, and CAUTION. These
words are used with the safety--alert symbol. DANGER identifies
the most serious hazards which will result in severe personal injury
or death. WARNING signifies hazards which could result in
personal injury or death. CAUTION is used to identify unsafe
practices which may result in minor personal injury or product and
property damage. NOTE is used to highlight suggestions which
will result in enhanced installation, reliability, or operation.
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Before installing or servicing system, always turn off main
power and tag disconnect to system. There may be more
than one disconnect switch. Turn off accessory heater power
switch if applicable.
!
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could result in personal
injury or equipment damage.
Puron (R--410A) systems operate at higher pressures than
standard R--22 systems. DO NOT use R--22 service
equipment or components on Puron (R--410A) equipment.
Ensure service equipment is rated for Puron (R--410A).
!
CAUTION
CUT HAZARD
Failure to follow this caution may result in personal injury.
When removing access panels or performing maintenance
functions inside your unit, be aware of sharp sheet metal parts
and screws. Although special care is taken to reduce sharp
edges to a minimum, be extremely careful and wear protective
clothing, safety glasses and gloves when handling parts or
reaching into the unit.
RECEIVING AND INSTALLATION
Step 1 — Check Equipment
IDENTIFY UNIT
The unit model number and serial number are printed on the unit
informative plate. Check this information against shipping papers.
INSPECT SHIPMENT
Inspect for shipping damage before removing packaging material.
If unit appears to be damaged or is torn loose from its anchorage,
have it examined by transportation inspectors before removal.
Forward claim papers directly to transportation company.
Manufacturer is not responsible for any damage incurred in transit.
Check all items against shipping list. Immediately notify the
nearest distributor’s office if any item is missing. To prevent loss or
damage, leave all parts in original packages until installation.
If the unit is to be mounted on a curb in a downflow application,
review Step 5 to determine which method is to be used to remove
the downflow panels before rigging and lifting into place. The
panel removal process may require the unit to be on the ground.
Step 2 — Provide Unit Support
IMPORTANT: The unit must be secured to the curb by installing
screws through the bottom of the curb flange and into the unit base
rails. When installing large base units onto the common curb, the
screws must be installed before allowing the full weight of the unit
to rest on the curb. A minimum of six screws are required for large
base units. Failure to secure unit properly could result in an
unstable unit. See Warning near Rigging/Lifting information and
accessory curb instructions for more details.
For hurricane tie downs, contact distributor for details and PE
(Professional Engineering) Certificate, if required.
ROOF CURB
Install accessory roof curb in accordance with instructions shipped
with curb (See Fig. 4). Install insulation, cant strips, roofing, and
flashing. Ductwork must be attached to curb.
IMPORTANT: The gasketing of the unit to the roof curb is
critical for a water tight seal. Install gasketing material supplied
with the roof curb. Improperly applied gasketing also can result in
air leaks and poor unit performance.
Curb should be level to within 1/4 in. (6.4 mm) (See Fig. 2). This
is necessary for unit drain to function properly. Refer to accessory
roof curb installation instructions for additional information as
required.
Installation on older “G” series roof curbs.
Two accessory kits are available to aid in installing a new “G”
series unit on an old “G” roof curb.
1. Accessory kit number CPADCURB001A00, (small chassis)
and accessory kit number CPADCURB002A00, (large
chassis) includes roof curb adapter and gaskets for the
perimeter seal and duct openings. No additional
modifications to the curb are required when using this kit.
2. An alternative to the adapter curb is to modify the existing
curb by removing the outer horizontal flange and use
accessory kit number CPGSKTKIT001A00 which includes
spacer blocks (for easy alignment to existing curb) and
gaskets for the perimeter seal and duct openings. This kit is
used when existing curb is modified by removing outer
horizontal flange.
2
CAUTION
!
UNIT/STRUCTURAL DAMAGE HAZARD
Failure to follow this caution may result in property damage.
Ensure there is sufficient clearance for saw blade when cutting
the outer horizontal flange of the roof curb so there is no
damage to the roof or flashing.
IMPORTANT: Do not restrict outdoor airflow. An air restriction
at either the outdoor--air inlet or the fan discharge may be
detrimental to compressor life.
Do not place the unit where water, ice, or snow from an overhang
or roof will damage or flood the unit. Do not install the unit on
carpeting or other combustible materials. Slab--mounted units
should be at least 2 in. (51 mm) above the highest expected water
and runoff levels. Do not use unit if it has been under water.
Step 4 — Rig and Place Unit
!
WARNING
PERSONAL INJURY OR PROPERTY DAMAGE
HAZARD
Failure to follow this warning could result in personal
injury, death or property damage.
C
When installing the unit on a rooftop, be sure the roof will
support the additional weight.
MAXIMUM ALLOWABLE
DIFFERENCE in. (mm)
B
A-B
B-C
A-C
1/4 (6.35)
1/4 (6.35)
1/4 (6.35)
A07925
Fig. 2 -- Unit Leveling Tolerances
SLAB MOUNT
Place the unit on a solid, level pad that is at least 2 in. (51 mm)
above grade. The pad should extend approximately 2 in. (51 mm)
beyond the casing on all 4 sides of the unit (See Fig. 3). Do not
secure the unit to the pad except when required by local codes.
OPTIONAL
RETURN
AIR
OPENING
OPTIONAL
SUPPLY
AIR
OPENING
2˝
(50.8mm)
EVAP. COIL
COND. COIL
Rigging and handling of this equipment can be hazardous for
many reasons due to the installation location (roofs, elevated
structures, etc.).
Only trained, qualified crane operators and ground support staff
should handle and install this equipment.
When working with this equipment, observe precautions in the
literature, on tags, stickers, and labels attached to the equipment,
and any other safety precautions that might apply.
Training for operators of the lifting equipment should include, but
not be limited to, the following:
1. Application of the lifter to the load, and adjustment of the
lifts to adapt to various sizes or kinds of loads.
2. Instruction in any special operation or precaution.
3. Condition of the load as it relates to operation of the lifting
kit, such as balance, temperature, etc.
Follow all applicable safety codes. Wear safety shoes and work
gloves.
INSPECTION
Prior to initial use, and at monthly intervals, all rigging shackles,
clevis pins, and straps should be visually inspected for any damage,
evidence of wear, structural deformation, or cracks. Particular
attention should be paid to excessive wear at hoist hooking points
and load support areas. Materials showing any kind of wear in
these areas must not be used and should be discarded.
A07926
!
Fig. 3 -- Slab Mounting Detail
Step 3 — Provide Clearances
WARNING
ELECTRICAL SHOCK HAZARD
The required minimum service clearances are shown in Fig. 5 and
6. Adequate ventilation and outdoor air must be provided. The
outdoor fan draws air through the outdoor coil and discharges it
through the top fan grille. Be sure that the fan discharge does not
recirculate to the outdoor coil. Do not locate the unit in either a
corner or under an overhead obstruction. The minimum clearance
under a partial overhang (such as a normal house overhang) is 48
in. (1219 mm) above the unit top. The maximum horizontal
extension of a partial overhang must not exceed 48 in. (1219 mm).
Failure to follow this warning could result in personal
injury or death.
Before installing or servicing system, always turn off main
power to system and install lockout tag. There may be
more than one disconnect switch. Turn off accessory heater
power switch if applicable. Tag disconnect switch with a
suitable warning label.
!
WARNING
UNIT FALLING HAZARD
Failure to follow this warning could result in personal
injury or death.
Never stand beneath rigged units or lift over people.
3
50XT-- A
A
Dashed lines show cross support
location for large basepan units.
B
G
HVAC unit
basepan
HVAC unit
base rails
C
Sealing
Gasket
Roofcurb
A
Anchor screw
H
F
Wood nailer*
Flashing field
supplied
Roofcurb*
Insulation
(field supplied)
Roofing material
field supplied
E
D
Cant strip
field supplied
50XT-- A
SMALL/COMMON CURB
A09413
*Provided with roofcurb
A09090
ROOF CURB DETAIL
B
C
SUPPLY
AIR
SMALL
BASE
UNIT
RETURN
AIR
LARGE
BASE
UNIT
G
H
F A
E
D
UNIT PLACEMENT ON
COMMON CURB
SMALL OR LARGE BASE UNIT
A09415
LARGE CURB
A09094
A09414
UNIT
SIZE
CATALOG
NUMBER
A
IN. (mm)
Small
or
Large
CPRFCURB010A00
11 (279)
CPRFCURB011A00
14 (356)
CPRFCURB012A00
11 (279)
CPRFCURB013A00
14 (356)
Large
B
(small /
common
base)
IN. (mm)*
B
(large base)
IN. (mm)*
C
IN. (mm)
10 (254)
14 (356)
16 (406)
D
IN. (mm)
47.8
(1214)
14 (356)
NOTES:
1. Roof curb must be set up for unit being installed.
2. Seal strip must be applied, as required, to unit being installed.
3. Roof curb is made of 16--gauge steel.
4. Attach ductwork to curb (flanges of duct rest on curb).
5. Insulated panels: 1--in. (25 mm) thick fiberglass 1 lb. density.
Fig. 4 -- Roof Curb Dimensions
4
E
IN. (mm)
32.4
(822)
43.9
(1116)
F
IN. (mm)
G
IN. (mm)
H
IN. (mm)
30.6 (778)
2.7 (69)
46.1 (1170)
42.2 (1072)
50XT-- A
A09543
Fig. 5 -- 50XT--A24--30 Unit Dimensions
5
50XT-- A
A09544
Fig. 6 -- 50XT--A36--60 Unit Dimensions
6
Rigging/Lifting of Unit
!
3. Attach a clevis of sufficient strength in the middle of the
straps. Adjust the clevis location to ensure unit is lifted level
with the ground.
4. After unit is placed on the roof curb or mounting pad,
remove the top skid.
WARNING
UNIT FALLING HAZARD
Failure to follow this warning could result in personal
injury or death.
!
Large base units must be secured to common curb before
allowing full weight of unit to rest on curb. Install screws
through curb into unit base rails while rigging crane is still
supporting unit.
WARNING
UNIT FALLING HAZARD
Failure to follow this warning could result in personal
injury/death or property damage.
When straps are taut, the clevis should be a minimum of 36
in. (914 mm) above the unit top cover.
Lifting holes are provided in base rails as shown in Fig. 5 and 6.
1. Leave top shipping skid on the unit for use as a spreader bar
to prevent the rigging straps from damaging the unit. If the
skid is not available, use a spreader bar of sufficient length
to protect the unit from damage.
2. Attach shackles, clevis pins, and straps to the base rails of
the unit. Be sure materials are rated to hold the weight of the
unit (See Fig. 7).
50XT-- A
After the unit is placed on the roof curb or mounting pad, remove
the top crating.
CAUTION - NOTICE TO RIGGERS
PRUDENCE - AVIS AUX MANIPULATEUR
ACCESS PANELS MUST BE IN PLACE WHEN RIGGING.
PANNEAUX D'ACCES DOIT ÊTRE EN PLACE POUR MANIPULATION.
Use top skid as spreader bar. / Utiliser la palette du haut comme barre de répartition
DUCTS
MINIMUM HEIGHT: 36" (914.4 mm)
HAUTEUR MINIMUM
SEAL STRIP MUST BE IN
PLACE BEFORE PLACING
UNIT ON ROOF CURB
UNIT HEIGHT
HAUTEUR D'UNITÉ
BANDE SCELLANT DOIT ÊTRE
EN PLACE AVANT DE PLACER
L'UNITÉ SUR LA BASE DE TOIT
DETAIL A
VOIR DÉTAIL A
SEE DETAIL A
VOIR DÉTAIL A
50CY502286 2.0
A09079
CABINET
Small
RIGGING WT
MODEL
50XT--- A24
50XT--- A30
50XT--- A36
Large
50XT--- A42
50XT--- A48
50XT--- A60
NOTE: See dimensional drawing for corner weight distribution.
Fig. 7 -- Suggested Rigging
7
lb
435
465
kg
197
211
501
513
529
572
227
233
240
259
Step 5 — Select and Install Ductwork
The design and installation of the duct system must be in
accordance with the standards of the NFPA for installation of
non--residence type air conditioning and ventilating systems,
NFPA 90A or residence type, NFPA 90B and/or local codes and
ordinances.
Select and size ductwork, supply--air registers, and return air grilles
according to ASHRAE (American Society of Heating,
Refrigeration, and Air Conditioning Engineers) recommendations.
The unit has duct flanges on the supply-- and return--air openings
on the side of the unit.
!
!
AND
Failure to follow this warning could result in personal
injury or death.
Before installing or servicing system, always turn off main
power to system and install lockout tag. There may be
more than one disconnect switch. Turn off accessory heater
power switch if applicable.
1. Open all electrical disconnects before starting any service
work.
2. Remove horizontal (metal) duct covers to access vertical
(downflow) discharge duct knockouts in unit basepan. (See
Fig. 8.)
ELECTRICAL
Failure to follow this warning could result in personal
injury or death.
!
For vertical supply and return units, tools or parts could
drop into ductwork. Install a 90 degree turn in the return
ductwork between the unit and the conditioned space. If a
90 degree elbow cannot be installed, then a grille of
sufficient strength and density should be installed to prevent
objects from falling into the conditioned space. Units with
electric heaters require 90 degree elbow in supply duct.
When designing and installing ductwork, consider the following:
1. All units should have field--supplied filters or accessory
filter rack installed in the return--air side of the unit.
Recommended sizes for filters are shown in Table 1.
2. Avoid abrupt duct size increases and reductions. Abrupt
change in duct size adversely affects air performance.
IMPORTANT: Use flexible connectors between ductwork and
unit to prevent transmission of vibration. Use suitable gaskets to
ensure weather tight and airtight seal. When electric heat is
installed, use fireproof canvas (or similar heat resistant material)
connector between ductwork and unit discharge connection. If
flexible duct is used, insert a sheet metal sleeve inside duct. Heat
resistant duct connector (or sheet metal sleeve) must extend 24--in.
(610 mm) from electric heater element.
3. Size ductwork for max possible air flow (See Table 1).
4. Seal, insulate, and weatherproof all external ductwork. Seal,
insulate and cover with a vapor barrier all ductwork passing
through conditioned spaces. Follow latest Sheet Metal and
Air Conditioning Contractors National Association
(SMACNA) and Air Conditioning Contractors Association
(ACCA) minimum installation standards for residential
heating and air conditioning systems.
5. Secure all ducts to building structure. Flash, weatherproof,
and vibration--isolate duct openings in wall or roof
according to good construction practices.
6. Read unit rating plate for any required clearances around
ductwork.
WARNING
ELECTRICAL SHOCK HAZARD
WARNING
PERSONAL
INJURY
OPERATION HAZARD
50XT-- A
CONVERTING HORIZONTAL DISCHARGE UNITS TO
DOWNFLOW (VERTICAL) DISCHARGE UNITS
WARNING
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in property
damage.
Collect ALL screws that were removed. Do not leave
screws on rooftop as permanent damage to the roof may
occur.
To remove downflow return and supply knockout covers, break
front and right side connecting tabs with a screwdriver and
hammer. Push cover down to break rear and left side tabs.
NOTE: These panels are held in place with tabs similar to an
electrical knockout. Reinstall horizontal duct covers (see Fig. 8)
shipped on unit from factory. Insure openings are air and
watertight.
NOTE: The design and installation of the duct system must be in
accordance with the standards of the NFPA for installation of non
residence--type air conditioning and ventilating systems, NFPA
90A or residence--type, NFPA 90B; and/or local codes and
ordinances.
Step 6 — Provide for Condensate Disposal
NOTE: Ensure that condensate water disposal methods comply
with local codes, restrictions, and practices.
The units dispose of condensate through a 3/4 --in. NPT female
fitting that exits on the compressor end of the unit. Condensate
water can be drained directly onto the roof in rooftop installations
(where permitted) or onto a gravel apron in ground level
installations. Install a field--supplied condensate trap at end of
condensate connection to ensure proper drainage. Make sure that
the outlet of the trap is at least 1 in. (25 mm) lower than the
drain--pan condensate connection to prevent the pan from
overflowing. Prime the trap with water. When using a gravel apron,
make sure it slopes away from the unit.
If the installation requires draining the condensate water away from
the unit, install a field--supplied 2--in. (51 mm) trap at the
condensate connection to ensure proper drainage. Condensate trap
is available as an accessory or is field--supplied. Make sure that the
outlet of the trap is at least 1 in. (25 mm) lower than the unit
drain--pan condensate connection to prevent the pan from
overflowing. Connect a drain tube using a minimum of
field--supplied 3/4 --in. PVC or field--supplied 3/4 --in. copper pipe
at outlet end of the 2 --in. (51 mm) trap (See Fig. 9). Do not
undersize the tube. Pitch the drain trough downward at a slope of at
least 1 in. (25 mm) for every 10 ft. (3.1 m) of horizontal run. Be
sure to check the drain tube for leaks. Prime the trap at the
beginning of the cooling season start--up.
8
HIGH--VOLTAGE CONNECTIONS
The unit must have a separate electrical service with a
field--supplied, waterproof disconnect switch mounted at, or within
sight from, the unit. Refer to the unit rating plate, NEC and local
codes for maximum fuse/circuit breaker size and minimum circuit
amps (ampacity) for wire sizing.
The field--supplied disconnect may be mounted on the unit over
the high--voltage inlet hole (See Fig. 5 and 6).
If the unit has an electric heater, a second disconnect may be
required. Consult the Installation, Start--Up, and Service
Instructions provided with the accessory for electrical service
connections.
Operation of unit on improper line voltage constitutes abuse and
may cause unit damage that could affect warranty.
!
Horizontal Duct Covers
A09076
UNIT COMPONENT DAMAGE HAZARD
Failure to follow this caution may result in damage to the
unit being installed.
1. Make all electrical connections in accordance with NEC
NFPA 70 (latest edition) and local electrical codes
governing such wiring. In Canada, all electrical
connections must be in accordance with CSA standard
C22.1 Canadian Electrical Code Part 1 and applicable
local codes. Refer to unit wiring diagram.
2. Use only copper conductor for connections between
field--supplied electrical disconnect switch and unit. DO
NOT USE ALUMINUM WIRE.
3. Be sure that high--voltage power to unit is within
operating voltage range indicated on unit rating plate.
4. Insulate low--voltage wires for highest voltage contained
within conduit when low--voltage control wires are in
same conduit as high--voltage wires.
5. Do not damage internal components when drilling
through any panel to mount electrical hardware, conduit,
etc.
Basepan
Downflow
(Vertical)
Return
Knockout
A09093
Fig. 8 -- Supply and Return Duct Opening
TRAP
OUTLET
1-in. (25 mm) min.
2-in. (51 mm) min.
A09052
Fig. 9 -- Condensate Trap
Step 7 — Install Electrical Connections
!
WARNING
ELECTRICAL SHOCK HAZARD
ROUTING POWER LEADS INTO UNIT
Use only copper wire between disconnect and unit. The high
voltage leads should be in a conduit until they enter the duct panel;
conduit termination at the duct panel must be watertight. Run the
high--voltage leads through the power entry knockout on the
power entry side panel. See Fig. 5 and 6 for location and size. For
single--phase units, connect leads to the black and yellow wires.
CONNECTING GROUND LEAD TO GROUND SCREW
Connect the ground lead to the chassis using the ground screw in
the wiring splice box (See Fig. 11).
Failure to follow this warning could result in personal
injury or death.
The unit cabinet must have an uninterrupted, unbroken
electrical ground. This ground may consist of an electrical
wire connected to the unit ground screw in the control
compartment, or conduit approved for electrical ground
when installed in accordance with NEC, NFPA 70 National
Fire Protection Association (latest edition) (in Canada,
Canadian Electrical Code CSA C22.1) and local electrical
codes.
9
50XT-- A
Basepan
Downflow
(Vertical)
Supply
Knockout
CAUTION
Table 1 – Physical Data -- Unit 50XT--A
UNIT SIZE
24
30
36
42
48
NOMINAL CAPACITY ton
2
2--1/2
3
3--1/2
4
5
435
197
465
211
501
227
513
233
529
240
572
259
10.3
(4.7)
11.5
(5.2)
9.7
(4.4)
14.0
(6.4)
15.5
(7.0)
16.0
(7.3)
0.042
0.038
0.035
0.040
0.038
0.046
N/A
0.038
0.035
0.040
0.046
0.046
SHIPPING WEIGHT (lb)
(kg)
60
Two--Stage Scroll
COMPRESSOR
REFRIGERANT (R--410A) Quantity (lb)
(kg)
AccuRater
EXPANSION DEVICE--HEATING
ORIFICE OD (in.) -- Left
ORIFICE OD (in.) -- Right
TXV
EXPANSION DEVICE--COOLING
Size
2 Ton
3 Ton
3 Ton
4 Ton
4 Ton
5 Ton
2…21
2…21
2…21
2…21
2…21
2…21
13.6
15.3
17.5
19.4
19.4
23.3
2700
2700
2800
2800
3300
3300
22
22
22
22
22
22
1/8 (825)
1/8 (825)
1/8 (825)
1/8 (825)
1/4 (1100)
1/3 (1110)
3…17
3…17
3…17
3…17
3…17
4…17
3.7
3.7
4.7
4.7
5.7
5.7
OUTDOOR COIL
Rows…Fins/in.
Face Area (sq. ft.)
OUTDOOR FAN
Nominal Cfm
50XT-- A
Diameter
Motor HP (RPM)
INDOOR COIL
Rows…Fins/in.
Face Area (sq. ft.)
INDOOR FAN
Nominal Airflow (Cfm)
Comfort
Variable based on Comfort Settings (see User Interface instructions for more information).
Efficiency
700
875
1050
1225
1400
Max
800
1000
1200
1400
1600
2000
10x10
(254x254)
10x10
(254x254)
11x10
(279x254)
11x10
(279x254)
11x10
(279x254)
11x10
(279x254)
1/2
1/2
3/4
3/4
3/4
1
Size in.
(mm)
Motor HP (RPM)
1750
HIGH--PRESSURE SWITCH (psig)
Cutout
670 ± 10
Reset (Auto)
470 ± 25
HIGH--PRESSURE SWITCH 2 (psig)
(Compressor Solenoid)
Cutout
565 ± 15
Reset (Auto)
455 ± 15
LOSS--OF--CHARGE/LOW--PRESSURE SWITCH
(Liquid Line) (psig)
Cutout
23 ± 5
Reset (Auto)
55 ± 5
RETURN--AIR FILTERS Throwaway in.*
20x24x1
24x30x1
24x36x1
(mm)
(508x610x25)
(610x762x25)
610x914x25)
*Recommended filter sizes for field---installed air filter grilles mounted on the wall or ceiling of the conditioned structure. Required filter sizes shown are based on
the larger of the AHRI (Air Conditioning Heating and Refrigeration Institute) rated cooling airflow or the heating airflow velocity of 300 ft (91.4 mm) /minute for
throwaway type or 450 (137 mm) ft/minute for high ---capacity type. Air filter pressure drop for non ---standard filters must not exceed 0.08 IN. W.C.
10
INDOOR
THERMOSTAT
RETURN
AIR
FROM
POWER
SOURCE
50XT-- A
TOP COVER
DISCONNECT
PER NEC
POWER ENTRY
CONTROL ENTRY
A09091
Fig. 10 -- Typical Installation
GROUND SCREW
(IN SPLICE BOX)
GROUND
LEAD
SINGLE-PHASE
CONNECTIONS
TO DISCONNECT
PER NEC
chassis ground through a printed circuit run at SEC2 and metal
control board mounting eyelets. Check to be sure control board is
mounted securely using both factory--installed screws.
Outdoor Air Temperature Sensor (OAT)
L1
BLK
L2
YEL
!
CAUTION
EQUIPMENT OPERATION HAZARD
Failure to follow this caution may result in improper unit
operation.
The installation of an outdoor air temperature sensor (OAT)
using the Infinity control board OAT terminals is required.
Many Infinity features (auto humidity control, comfort
rollback, etc.) will be lost if the OAT is not connected.
For detailed mounting instructions for the OAT sensor,
please refer to installation instructions shipped with the
OAT.
NOTE: Use copper wire only.
LEGEND
NEC – National Electrical Code
Field Wiring
Splice Connections
A06299
Fig. 11 -- Line Power Connections
ROUTING CONTROL POWER WIRES
For detailed instruction on the low voltage connections to the User
Interface (UI), refer to the UI installation guide.
Form a drip--loop with the control leads before routing them into
the unit. Route the low voltage control leads through grommeted,
low--voltage hole provided into unit (See Fig. 5 and 6). Connect
user interface leads to unit control power leads as shown in Fig. 14.
The unit transformer supplies 24--v power for complete system
including accessory electrical heater. A circuit breaker is provided
in the 24--v circuit as a protection device (See Fig. 17); see the
caution label on the transformer. Transformer is factory wired for
230--v operation. If supply voltage is 208--v, rewire transformer
primary as described in Special Procedures for 208--v Operation
section.
The fan coil board is fused by a board--mounted automotive fuse
placed in series with transformer SEC1 and R circuit (See F1 on
Fig. 15). The C circuit of transformer circuit is referenced to
The OAT input is used to supply outdoor temperature data for
system level functions and for temperature display on UI. Using
two wires of the field--supplied thermostat wire cable, wire the ends
of the two black OAT pigtails. Wire the opposite ends of these two
wires to the OAT provided with the UI. There is no polarity to be
observed.
NOTE: Mis--wiring OAT inputs will not cause damage to either
Infinity control or thermistor. If the thermistor is wired incorrectly,
no reading will appear at UI. Re--wire thermistor correctly for
normal operation.
Two options for mounting the OAT sensor
1. Adjacent Building Structure
2. Under the Unit
Option 1: Mounting Sensor to the Adjacent
Building Structure
1. The recommended wall for mounting the sensor is the north
side of the building. The mounting height should be at 2 to
11
50XT-- A
3 ft above ground level, or all the way up into the eave. The
effect on the sun warming on the 3 walls (i.e. South, West
and East) can produce unacceptable temperature errors
under the right conditions. The sensor should be mounted
inside an ordinary or weatherproof outlet box. (See Fig. 12.)
2. Remove the Control access panel. The OAT Package is in a
bag located in Controls compartment. (See Fig. 13.)
3. Use the supplied clip, snap the sensor into the clip making
sure most of the sensor remains exposed, (not fully covered
by the clip). Ensure the mounting surface where the clip and
sensor will be located is clean and dry. To place the clip and
sensor, remove the protective paper exposing the clips
adhesive. Place on desired surface and hold in place for 5 to
10 seconds, ensuring positive contact.
4. Using the supplied wire nuts, connect sensor with splice
wires as required. Solid thermostat or stranded, 22 AWG (or
heavier wire) may be used for splicing. Connections should
be located within an outlet box or within the inside wall
(check your local codes). (See Fig. 12.)
5. Route the sensor wires around the unit through the control
wires entry. Connect the sensor wires to the black wire
pigtails in the control compartment. (See Fig. 13 and Fig.
14.)
Advantages:
S This is the most accurate way of reading outdoor temperature.
Disadvantages:
S This application requires dedicated wire between the sensor
location and the indoor termination point.
FIELD-SUPPLIED
OUTLET BOX
COVER
EXTERIOR
WALL
SENSOR
A98288
Fig. 12 -- Mounting Sensor to Outside Wall
Option 2: Mounting Sensor Under the Outdoor
Unit
1. The sensor should be mounted under the northeast corner of
the unit. Mount the sensor on the unit in the area not
exposed to sunlight.
2. Remove the Control access panel. The OAT Package is in a
bag located in Controls compartment. (See Fig. 13.)
3. Using the supplied clip, snap the sensor into the clip making
sure most of he sensor remains exposed, (not fully covered
by the clip). Ensure the mounting surface where the clip and
sensor will be located is clean and dry. To place the clip and
sensor, remove the protective paper exposing the clips
adhesive. Place on desired surface and hold in place for 5 to
10 seconds, ensuring positive contact.
4. Using the supplied wire nuts, connect sensor with splice
wires as required. Solid thermostat or stranded, 22 AWG (or
heavier wire) may be used for splicing. Connections should
be located within an outlet box (check your local codes).
Sensor and wires must be protected from the damage due to
animals and power equipment.
5. Route the sensor wires around the unit through the control
wires entry. Connect the sensor wires to the black wire
pigtails in the control compartment. (See Fig. 13 and Fig.
14.)
Advantages:
S Convenient mounting and wiring of outdoor air temperature
sensor.
Disadvantages:
S The sun may have some effect when unit is not running.
S Defrost cycle (if heat pump) can introduce a small temperature
error while defrosting.
S Snow and ice buildup under the outdoor unit may introduce
error.
S Landscaping around outdoor unit may affect temperature
reading.
ACCESSORY INSTALLATION
A. Accessory Electric Heaters
Electric heaters may be installed in 50XT--A per instructions
supplied with electric heater package. See unit rating plate for
factory--approved electric heater kits.
NOTE:
Units installed without electric heat should have a
factory--supplied sheet metal block--off plate installed over heater
opening. This reduces air leakage and formation of exterior
condensation.
B. Humidifier Connections
The fan coil control board terminal marked HUM is provided for
low voltage (24--vac) control of a humidifier. No humidistat is
required as UI monitors indoor humidity.
When commanded to operate humidifier, the unit control will
energize the HUM output to turn humidifier on and de--energize
HUM output to turn humidifier off. Wire HUM and C terminals
directly to humidifier as shown in Fig. 14.
SPECIAL PROCEDURES FOR 208--V OPERATION
Be sure unit disconnect switch is open.
Disconnect the yellow primary lead from the transformer. See unit
wiring label (See Fig. 17).
Connect the yellow primary lead to the transformer terminal
labeled 200--v.
12
HP/AC
BOARD
TWO BLACK WIRES TO
CONNECT OAT SENSOR
50XT-- A
OAT PACKAGE
FAN COIL
BOARD
A12247
Fig. 13 -- Control Plate
User
Interface
A
Infinity Fan Coil
Board
Infinity HP/AC
Board
B
A
B
A
B
C
D
C
D
C
D
Outdoor Air Thermistor
(Supplied with UI)
FIELD CONNECTION
REQUIRED
(BLACK WIRES)
OAT
R
Y
OCT
O
HUMIDIFIE R
(24 VAC)
W
C
Outdoor Coil Thermistor
FACTORY CONNECTE D
HUM
O
Y2
Y1
W1
C
R
LEGEND
Factory Wiring
Field Wiring
VIO
FACTORY WIRES PROV IDED
FOR FIELD CONNE CTION
OF UTILITY CURTA ILME NT
PNK
A06281
Fig. 14 -- Control Voltage Wiring Connections
13
PRE--START--UP
WARNING
D
C
SEC-1
HUM C W O Y R
1
OAT
1
COMM
1
A
B
SEC-2
STATUS
NOTE: Always check high-- and low--voltage supply to the unit
components. Check the integrity of the plug receptacle connections
and unit wiring harness prior to assuming a component failure.
A. LED Description
LEDs built into Infinity control boards provide installer or service
person information concerning operation and/or fault condition of
the unit controls and the Indoor Fan ECM motor. This information
is also available at the system UI in text with basic troubleshooting
instructions. Careful use of information displayed will reduce the
need for extensive manual troubleshooting.
Both the Fan Coil and Heat Pump (HP)/Air Conditioner (AC)
boards have an amber LED and a green LED located near the
System Communications connector (ABCD) (upper right center of
the Fan Coil board, lower right corner of the HP/AC board as
installed in the unit). The amber LED is the System Status LED,
labeled STATUS. The green LED, labeled COMM, is used as an
indicator of system communications status (See Fig. 14 and Fig.
15).
HEATER
Use the Start--Up Checklist supplied at the end of this book and
proceed as follows to inspect and prepare the unit for initial
start--up:
1. Remove all access panels.
2. Read and follow instructions on all DANGER, WARNING,
CAUTION, and INFORMATION labels attached to, or
shipped with unit.
3. Make the following inspections:
a. Inspect for shipping and handling damages, such as
broken lines, loose parts, disconnected wires, etc.
b. Inspect for oil at all refrigerant tubing connections and
on unit base. Detecting oil generally indicates a
refrigerant leak. Leak test all refrigerant tubing
connections using electronic leak detector, or
liquid--soap solution. If a refrigerant leak is detected, see
following Check for Refrigerant Leaks section.
c. Inspect all field-- and factory--wiring connections. Be
sure that connections are completed and tight.
d. Ensure wires do not touch refrigerant tubing or sharp
sheet metal edges.
e. Inspect coil fins. If damaged during shipping and
handling, carefully straighten fins with a fin comb.
4. Verify the following conditions:
a. Make sure that outdoor fan blade is correctly positioned
in fan orifice (See Fig. 20).
b. Make sure that condensate drain pan and trap are filled
with water to ensure proper drainage.
c. Make sure that all tools and miscellaneous loose parts
have been removed.
5. Compressors are internally spring mounted. Do not loosen
or remove compressor holddown bolts.
Step 1 — Unit Start--Up
5
Failure to follow this warning could result in personal
injury or death and/or property damage.
1. Follow recognized safety practices and wear protective
goggles when checking or servicing refrigerant system.
2. Do not operate compressor or provide any electric power
to unit unless compressor terminal cover is in place and
secured.
3. Do not remove compressor terminal cover until all
electrical sources are disconnected and tagged.
4. Relieve and recover all refrigerant from system before
touching or disturbing anything inside terminal box if
refrigerant leak is suspected around compressor
terminals.
5. Never attempt to repair soldered connection while
refrigerant system is under pressure.
6. Do not use torch to remove any component. System
contains oil and refrigerant under pressure.
7. To remove a component, wear protective goggles and
proceed as follows:
a. Shut off electrical power to unit and install
lockout tag.
b. Relieve and reclaim all refrigerant from system
using both high-- and low--pressure ports.
c. Cut component connecting tubing with tubing
cutter and remove component from unit.
d. Carefully unsweat remaining tubing stubs when
necessary. Oil can ignite when exposed to flame.
START--UP
F1
50XT-- A
FIRE, EXPLOSION, ELECTRICAL SHOCK AND
ENVIRONMENTAL HAZARD
1
!
6. Each unit system has two Schrader--type ports, one
low--side Schrader fitting located on the suction line, and
one high--side Schrader fitting located on the compressor
discharge line. Be sure that caps on the ports are tight.
MOTOR
A03169
Fig. 15 -- Detail of Fan Coil Board
Status Codes will be displayed on the STATUS LED using the
following protocol:
1. The number of short flashes indicates first digit of code.
2. The number of long flashes indicates second digit of code.
3. A short flash is 0.25 seconds on. A long flash is 1 second
on.
4. The time between flashes is 0.25 seconds.
5. The time between last short flash and first long flash is 1
second.
6. The LEDs will be off for 2.5 seconds before repeating code.
7. If multiple status codes are active concurrently, the highest
priority status code is displayed.
On the Fan Coil board, a second amber LED located at the bottom
center of the control board, adjacent to the motor harness plug, is
the motor status LED, labeled MOTOR. The motor status LED
will flash during normal blower operation.
14
50XT-- A
UTILITY RELAY
*
LLS
Liquid Line Solenoid
UTILITY SIGNAL
OPEN RELAY
* SUPPLIED BY UTILITY PROVIDER
A05247
Fig. 16 -- 2--Stage HP/AC Control Board
B. Control
Start--Up
and
System Communications
Troubleshooting
On power up, green COMM LEDs will be turned off until
successful system communications are established (this should
happen within 10 seconds). Once communications with UI are
successful, both COMM LEDs will be lit and held on. At the same
time, amber STATUS LEDs will be lit and held continuously on
until a request for operating mode is received. The STATUS LED
will be on any time unit is in idle mode.
If, at any time, communications are not successful for a period
exceeding 2 minutes, the Infinity control will only allow
emergency heating or cooling operation using a common
thermostat and the terminal strip connections on the two control
boards (see Non--Communicating Emergency Cooling/Heating
Mode) and will display Status Code 16, System Communication
Fault, on amber STATUS LED. No further troubleshooting
information will be available at UI until communications are
re--established.
If either COMM LED does not light within proper time period and
status codes are not displayed;
1. Check system transformer high-- and low--voltage to be sure
the system is powered.
2. Check ABCD connection on both boards.
3. Check fuse on fan coil board to be sure it is not blown. If
fuse is open, check system wiring before replacing it to be
sure a short does not cause a failure of replacement fuse.
If COMM LED does not light within proper time period and status
code is displayed,
1. Check system wiring to be sure UI is powered and
connections are made A to A, B to B, etc. and wiring is not
shorted. Mis--wiring or shorting of the ABCD
communications wiring will not allow successful
communications.
NOTE: Shorting or mis--wiring low--voltage system wiring will
not cause damage to unit control or UI but may cause low voltage
fuse to open.
C. Indoor Fan Motor (IFM) Troubleshooting
The indoor fan is driven by an Electronic Computated Motor
(ECM) which consists of two parts: the control module and the
motor winding section. Do not assume motor or module is
defective if it will not start. Use the designed--in LED information
aids and follow troubleshooting steps described below before
replacing motor control module or entire motor. Motor control
module is available as a replacement part.
VERIFY MOTOR WINDING SECTION
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
After disconnecting power from the ECM motor, wait at
least 5 minutes before removing the control section. Internal
capacitors require time to discharge.
Before proceeding to replace a motor control module:
1. Check motor winding section to be sure it is functional.
2. Remove motor control module section and unplug winding
plug. Motor shaft should turn freely, resistance between any
two motor leads should be similar and resistance between
any motor lead and unpainted motor end should exceed
100,000 ohms.
3. Failing any of these tests, entire ECM motor must be
replaced.
4. Passing all of the tests, motor control module alone can be
replaced.
15
50XT-- A
A10218
Fig. 17 -- Wiring Schematic--50XT--A Single Phase
16
Fan coil control is constantly communicating with the motor, even
when the motor and MOTOR LED are off. If motor does not
acknowledge receipt of communications, the fan coil control will
display Status Code 44 on STATUS LED and continue to try to
communicate with the motor. If motor acknowledges
communication, status code will be cleared.
If MOTOR LED is lit and flashing and motor does not run:
1. Check the STATUS LED. If STATUS LED is indicating a
Status 44 code, check the motor wiring harness for proper
connection to control and motor receptacles.
2. Check motor wiring harness to be sure all wiring complies
with wiring diagram description, makes a complete circuit
from connector to connector, and is not shorted.
3. Check 12--vdc low voltage supply to motor at pins 1 (+)
and 2 (--) of motor header connection to fan coil control.
If all checks are normal, fan coil control is good and control
module on motor may need replacement. Check motor and Motor
Control Module following the instructions in Section C, Indoor
Fan Motor Troubleshooting.
If the MOTOR LED is off, STATUS LED is indicating a Status
Code 44 and motor is running:
1. Disconnect the motor harness at the fan coil control. If
motor continues to run, fan coil control is good and control
module on motor may need replacement.
STATUS CODE 25, INVALID MOTOR / MODEL SELECTION
On initial start--up, the fan coil control shall poll motor for its size
data and check unit size data stored in the control memory.
1. If motor size is incorrect for unit size or size data is invalid,
Status Code 25 will be displayed on STATUS LED.
2. If model size data is missing (as is the case when a
replacement fan coil control board is installed), system UI
will prompt installer to enter correct model size from a list
of valid sizes.
3. If motor size is incorrect for model size, motor must be
replaced with proper size motor. Fan coil control will not
respond to operation requests until this fault condition is
resolved.
STATUS CODE 26, INVALID HEATER SIZE
On initial power--up, fan coil control will write into memory
electric heater size as read from heater if heater is provided with
Identifier Resistor (IDR). Heater size must be valid for the installed
unit. Fan coil control will read IDR value connected to pins 1 and 2
of heater harness connector. If no resistor is found, system UI will
prompt installer to verify that no heater is installed. Verifying that
this is correct will establish that the unit is operating without an
electric heater accessory. Upon choosing negative option, installer
will be prompted to select heater size installed from a list of valid
heater sizes for unit size installed.
If heater ID resistor value read is invalid, Status Code 26 will be
displayed on STATUS LED.
If heater installed is equipped with a resistor connected to pins 1
and 2 of heater harness connector and status code 26 is displayed
on STATUS LED:
1. Check wiring harness connections to be sure connections
are secure.
2. If symptoms persist, disconnect wiring harness at fan coil
control board and check for a resistance value greater than
5000 ohms.
3. Check for proper wiring of resistor assembly.
4. Make sure heater size installed is an approved size for unit
and size installed.
NOTE: Fan coil control will not operate electric heater until this
Status Code is resolved. If the heater size is set through the UI, the
heater will be operated as a single stage heater. If staging is desired,
the IDR value must be read in by the unit control.
17
50XT-- A
MOTOR TURNS SLOWLY
1. Low static pressure loading of blower while access panel is
removed will cause blower to run slowly. Particularly at low
airflow requests. This is normal, do not assume a fault
exists.
2. Recheck airflow and system static pressure using UI service
screens with access panel in place.
NOTE: Blower motor faults will not cause a lockout of blower
operation. The fan coil control will attempt to run the blower motor
as long as UI maintains a demand for airflow. The control will not
operate electric heaters while a fault condition exists. The control
communicates with the motor at least once every five seconds,
even when the motor is idle. If, during operation, the control does
not communicate with the motor for more than 25 seconds, the
motor will shut itself down and wait for communications to be
reestablished.
D. Using Fan Coil Control Motor LED in Troubleshooting
The MOTOR LED is connected to the blower motor
communication line and works with the fan coil control
microprocessor and the STATUS LED to provide unit operation
and troubleshooting information. When the motor is commanded
to operate, the MOTOR LED will be turned on and will flash each
time instructions are sent to the motor. When the motor is
commanded to stop, the MOTOR LED will be turned off.
If the MOTOR LED is lit, flashing, and the motor is running, or if
the MOTOR LED is off and the motor is stopped, operation is
normal and no motor fault exists.
If the MOTOR LED is lit, flashing, and the motor does not run, or
if the MOTOR LED is off and the motor is running, check the
STATUS LED for the Status Code. Refer to the troubleshooting
instructions for the indicated Status Code in Section E, Fan Coil
Control Troubleshooting.
E. Fan Coil Control Troubleshooting
Fan coil control faults indicated by flashing codes on the amber
system STATUS LED can be resolved using troubleshooting
information provided below. Codes are listed in order of their
priority, highest to lowest. Though multiple faults can exist at any
time, only the highest priority code will be displayed on STATUS
LED. Clearing the indicated fault when multiple faults exist will
cause the next highest priority Status Code to be flashed. All
existing faults, as well as a fault history, can be viewed at UI.
STATUS CODE 45, CONTROL BOARD TEST FAULT
Fan coil control has failed internal start--up tests and must be
replaced. No other service procedure will correct.
STATUS CODE 37, HEATER OUTPUT SENSED “ON” WHEN
NOT ENERGIZED:
Fan coil control is provided with circuitry to detect presence of a
24--vac signal on electric heater stage 1 and stage 2 outputs.
If fan coil control detects a 24--vac signal on either heater stage
output and it is not supplying signal, Status Code 37 will be
displayed on STATUS LED. Control will turn off output and
command blower motor to supply an airflow determined to be safe
for current operation mode with electric heaters energized.
To find the fault:
1. Stop all system operations at UI and check heater stage
24--vac outputs.
2. Disconnect electric heater at power and check heater wiring
for faults. See Status Code 36 for more information.
STATUS CODE 44, MOTOR COMMUNICATION FAULT
When motor is commanded to operate, the MOTOR LED will be
turned on and will flash each time instructions are sent to the
motor.
When the motor is commanded to stop, the MOTOR LED will be
turned off. The MOTOR LED will not flash to indicate
communications when it is turned off.
50XT-- A
STATUS CODE 36, HEATER OUTPUT NOT SENSED WHEN
ENERGIZED
Fan coil control is provided with circuitry to detect presence of a
24--vac signal on electric heater stage 1 and stage 2 outputs.
If fan coil control energizes either heater stage and does not detect
the 24--vac signal on output, Status Code 36 will be displayed on
the STATUS LED, control will continue to energize heater
output(s) and adjust blower operation to a safe airflow level for
energized electric heat stage(s).
To find the fault:
1. Check for 24--vac on heater stage outputs. Fan coil control
or sensing circuit may be bad.
NOTE: It may be useful as an electric heater troubleshooting
procedure to disconnect the system communications to force Status
Code 16 enabling of emergency heat mode. It is difficult to know
which heater output is energized or not energized in normal
operation. When unit is operated in emergency heat mode using
electric heaters, both outputs are energized and de--energized
together. Terminal strip inputs to fan coil control can then be
connected R to W to turn on both electric heat outputs. Heater
output sensing circuits can then be checked to resolve Status Code
36 or 37 problems.
STATUS CODE 41, BLOWER MOTOR FAULT
If MOTOR LED is lit and flashing and motor does not run:
1. Check STATUS LED. If STATUS LED is indicating Status
Code 41, motor control has detected that the motor will not
come up to speed within 30 seconds of being commanded
to run or that the motor has been slowed to below 250 rpm
for more than 10 seconds after coming up to speed. Motor
wiring harness and fan coil control are operating properly,
do not replace.
2. Check to be sure that the blower wheel is not rubbing the
housing.
3. Check motor to be sure that the motor shaft is not seized
(motor control module must be removed and electronics
disconnected from windings to perform this check
properly).
4. Check motor windings section following instructions in
Section C, Indoor Fan Motor Troubleshooting.
If all these checks are normal, the motor control module may need
replacement.
STATUS CODE 16, SYSTEM COMMUNICATION FAULT
If, at any time, system communications are not successful for a
period exceeding 2 minutes, the fan coil control will only allow
emergency heating or cooling operation using a common
thermostat, and the terminal strip connections and will display
Status code 16 on the amber STATUS LED (see
Non--Communicating Emergency Cooling/Heating Mode). No
further unit troubleshooting information will be available at the UI
until communications are re--established.
Check system wiring to be sure the UI is powered and connections
are made A to A, B to B, etc., and wiring is not shorted.
Mis--wiring or shorting of the ABCD communications wiring will
not allow successful communications. Correcting wiring faults will
clear the code and re--establish communications.
Shorting or mis--wiring the low voltage system wiring will not
cause damage to unit control or to UI but may cause the low
voltage fuse to open.
STATUS CODE 46, BROWNOUT CONDITION
If the secondary voltage of the transformer falls below 15--vac for a
period exceeding 4 seconds, Status Code 46 will be displayed on
STATUS LED and the UI will command the control board to turn
off compressor.
When secondary voltage rises above 17--vac for more than 4
seconds, the brownout condition is cleared and normal system
operation will resume subject to any minimum compressor
off--delay function which may be in effect. Brownout does not
affect blower or electric heater operation.
STATUS CODE 53, OUTDOOR AIR TEMPERATURE
SENSOR FAULT
If an OAT sensor is found at power--up, input is constantly checked
to be within a valid temperature range. If sensor is found to be
open or shorted at any time after initial validation, Status Code 53
will be displayed at amber STATUS LED.
Check for faults in wiring connecting sensor to OAT terminals.
Using an Ohm meter, check resistance of thermistor for a short or
open condition.
If thermistor is shorted or open, replace it to return the system to
normal operation. If fault is in the wiring connections, correcting
the fault will clear the code and return the system to normal
operation.
NOTE: If fault condition is an open thermistor or a wiring problem
that appears to be an open thermistor and the power to the unit is
cycled off, the fault code will be cleared on the next power--up but
the fault will remain and system operation will not be as expected.
This is because on power--up, the unit control cannot discern
the difference between an open sensor or if a sensor is not
installed.
F. HP/AC Control Troubleshooting
See Table 2 for HP/AC control board status codes and
troubleshooting information.
Step 2 — Sequence of Operation
The 50XT--A packaged heat pump is designed for installation with
a communicating UI. This unit will not respond to commands
provided by a common thermostat except under certain emergency
situations described in Step 1—Start--Up.
The UI uses temperature, humidity and other data supplied from
indoor and outdoor system components to control heating or
cooling system for optimum comfort. The unit will be commanded
by UI to supply airflow. The unit will operate the indoor fan at
requested airflow for most modes.
The nominal requested airflow will be 350 cfm per ton of nominal
cooling capacity as defined by unit size. Actual airflow request will
be adjusted from nominal using indoor and outdoor temperature
and indoor humidity data to optimize the system operation for
occupant comfort and system efficiency. Refer to UI literature for
further system control details.
Airflow during electric heater operation must be greater than a
minimum level for safe operation. If UI instructs unit to turn on
electric heat and the requested airflow is less than the minimum
level the fan coil control will override requested value.
NOTE: Once the compressor has started and then has stopped, it
should not be started again until 4 minutes have elapsed. The
cooling cycle remains “on” until the room temperature drops to
point that is slightly below the cooling control setting of the UI.
18
Table 2 – Heat Pump/Air Conditioner Board Status Codes
Normal operation.
None
None
2, pause
Normal operation.
FAULT
Standby – no call for unit operation
None
Emergency Mode
Standard Thermostat Control
Low Stage Cool/Heat Operation
High Stage Cool/Heat Operation
System Communications Failure
Invalid Model
Plug
High--- Pressure
Switch Open
Low--- Pressure
Switch Open
16
Control Fault
45
Brown Out
(230 v)
46
No 230v at Unit
47
Outdoor Air
Temp Sensor
Fault
Outdoor Coil
Sensor Fault
Thermistors Out
of Range
25
31
32
53
55
56
Low Stage Thermal Cutout
71
High Stage Thermal Cutout
72
Contactor
Shorted
73
No 230V at
Compressor
Low Stage Thermal Lockout
High Stage Thermal Lockout
74
81
82
Low--- Pressure
Lockout
83
High--- Pressure
Lockout
84
COOLING AND HEATING OPERATION
With a call for first stage cooling, the outdoor fan, reversing valve,
and low stage compressor are energized. If low--stage cannot
satisfy cooling demand, high--stage cooling is energized by the UI.
After second stage is satisfied, the unit returns to low--stage
operation until first stage is satisfied or until second stage is
required again. When both first stage and second stage cooling are
satisfied, the compressor will shut off. The reversing valve will
remain energized until the control board power is removed or a call
for heating in initiated. With a call for heating, the outdoor fan and
compressor are energized. The compressor will operate in high or
low stage operation, as needed to meet the heating demand. When
POSSIBLE CAUSE AND ACTION
Unit being controlled by standard thermostat inputs instead of Infinity Control. Only high stage operation is available. This operating
mode should be used in emergency situations only.
Normal operation.
Communication with UI lost. Check wiring to UI, indoor and outdoor
units.
Control does not detect a model plug or detects an invalid model
plug. Unit will not operate without correct model plug.
High--- pressure switch trip. Check refrigerant charge, outdoor fan
operation and coils for airflow restrictions.
Low--- pressure switch trip. Check refrigerant charge and indoor air
flow.
Outdoor unit control board has failed. Control board needs to be
replaced.
Line voltage < 187v for at least 4 seconds. Compressor and fan
operation not allowed until voltage>190v. Verify line voltage.
There is no 230v at the contactor when indoor unit is powered and
cooling/heating demand exists. Verify the disconnect is closed and
230v wiring is connected to the unit.
Outdoor air sensor not reading or out of range. Ohm out sensor
and check wiring.
Coil sensor not reading or out of range. Ohm out sensor and check
wiring.
Improper relationship between coil sensor and outdoor air sensor.
Ohm out sensors and check wiring.
Compressor voltage sensed, then disappears while cooling or heating demand exists. Possible causes are internal compressor overload trip or start relay not releasing (if installed).
Compressor voltage sensed, then disappears while cooling or heating demand exists. Possible causes are internal compressor overload trip or start relay not releasing (if installed).
Compressor voltage sensed when no demand for compressor operation exists. Contactor may be stuck closed or there is a wiring
error.
Compressor voltage not sensed when compressor should be starting. Contactor may be stuck open or there is a wiring error.
Thermal cutout occurs in three consecutive low/ high stage cycles.
Low stage locked out for 4 hours or until 24v power recycled.
Thermal cutout occurs in three consecutive high/low stage cycles.
High stage locked out for 4 hours or until 24v power recycled.
Low--- pressure switch trip has occurred during 3 consecutive
cycles. Unit operation locked out for 4 hours or until 24v power
recycled.
High--- pressure switch trip has occurred during 3 consecutive
cycles. Unit operation locked out for 4 hours or until 24v power
recycled.
the heating demand is satisfied, the compressor and fan will shut
off. The reversing valve is de--energized in the heating mode.
NOTE: When two--stage unit is operating at low--stage, system
vapor (suction) pressure will be higher than a standard single--stage
system or high--stage operation.
NOTE:
Outdoor fan motor will continue to operate for one
minute after compressor shuts off, when outdoor ambient is greater
than or equal to 100°F (38°C).
UTILITY INTERFACE WITH INFINITY CONTROL
The utility curtailment relay should be connected to factory
supplied pigtails (PINK, connected to R, VIOLET connected to Y2
on the control board) located in the low voltage splice box (See
19
50XT-- A
OPERATION
AMBER
LED
FLASH
CODE
On solid,
no flash
Rapid, continuous
flashing
1, pause
50XT-- A
Fig. 14, 16 and 17). This input allows a power utility device to
interrupt compressor operation during peak load periods. When the
utility sends a signal to shut the system down, the UI will display
“Curtailment Active”.
COMPRESSOR OPERATION
When the compressor is operating in low stage, the modulating
ring is de--activated, allowing two internal bypass ports to close off
33% of the scroll compression area so the system operates at part
load capacity. The 24--volt solenoid coil is de--energized in
low--stage operation.
When the compressor is operating at high stage, the modulating
ring is activated, sealing the bypass ports, which allows the
compressor to operate at full load capacity. The 24--volt solenoid
coil is energized in high stage operation.
CRANKCASE HEATER OPERATION (IF APPLICABLE)
The crankcase heater is energized during off cycle below 65_F
(18_C) outdoor air temperature.
OUTDOOR FAN MOTOR OPERATION
The outdoor unit control energizes the outdoor fan any time the
compressor is operating, except for defrost. The outdoor fan
remains energized if a pressure switch or compressor overload
should open. Outdoor fan motor will continue to operate for one
minute after the compressor shuts off when the outdoor ambient is
greater than or equal to 100_F (38_C).
TIME DELAYS
The unit time delays include:
S Five minute time delay to start cooling or heating operation
when there is a call from the thermostat or user interface. To
bypass this feature, momentarily short and release Forced
Defrost pins.
S Five minute compressor re--cycle delay on return from a
brown--out condition.
S Two minute time delay to return to standby operation from last
valid communication (with Infinity only).
S One minute time delay of outdoor fan at termination of cooling
mode when outdoor ambient is greater than or equal to 100_F
(38_C).
S Fifteen second delay at termination of defrost before the
auxiliary heat (W1) is de--energized.
S Twenty second delay at termination of defrost before the outdoor
fan is energized.
S Thirty second compressor delay when quiet shift enabled.
S There is no time delay between staging from low to high and from
high to low capacity; the compressor will change from low to high
and from high to low capacity as demand dictates.
INFINITY CONTROLLED LOW AMBIENT COOLING
NOTE: When this unit is operating below 55_F (13_C) outdoor
temperature, provisions must be made for low ambient operation.
This unit is capable of low ambient cooling down to 0_F (18_C)
ONLY when using the Infinity control. A low ambient kit is not
required, and the outdoor fan motor does not need to be replaced
for Infinity controlled low ambient operation. Low ambient
cooling must be enabled in the UI set--up. Fan may not begin to
cycle until about 40_F (4_C) OAT. Fan will cycle based on coil
and outdoor air temperature. Infinity controlled low ambient mode
operates as follows:
S In high stage, fan is off when outdoor coil temp is <outdoor air
temperature plus 3_F (1.6°C) or outdoor fan has been ON for 30
minutes. (Fan is turned off to allow refrigerant system to
stabilize.)
S In low stage, fan is off when outdoor coil temp is <outdoor air
temperature plus 1_F (--6°C)or outdoor fan has been ON for 30
minutes. (Fan is turned off to allow refrigerant system to
stabilize.)
S In high stage and low stage, fan is on when outdoor coil temp >
outdoor air temperature plus 25_F (13.8°C) or outdoor coil temp
> 80_F (27_C) or if outdoor fan has been OFF for 30 minutes.
(Fan is turned on to allow refrigerant system to stabilize.)
S Low--pressure switch is ignored for first 3 minutes during low
ambient start up. After 3 minutes, if LPS trips, then outdoor fan
motor is turned off for 10 minutes, with the compressor running.
If LPS closes within 10 minutes then cooling continues with the
outdoor fan cycling per the coil temperature routine listed above
for the remainder of the cooling cycle. If the LPS does not close
within 10 minutes, then the normal LPS trip response (shut down
cooling operation and generate LPS trip error) will occur.
DEFROST
This control offers 5 possible defrost interval times: 30, 60, 90, 120
minutes, or AUTO.
The defrost interval times: 30, 60, 90, and 120 -- minutes or AUTO
(default) are selected by the Infinity Control User Interface (the dip
switches are not used.)
AUTO defrost adjusts the defrost interval time based on the last
defrost time as follows:
S When defrost time <3 minutes, the next defrost interval=120
minutes.
S When defrost time 3--5 minutes, the next defrost interval=90
minutes.
S When defrost time 5--7 minutes, the next defrost interval=60
minutes.
S When defrost time >7 minutes, the next defrost interval=30
minutes.
The HP/AC control board accumulates compressor run time. As
the accumulated run time approaches the selected defrost interval
time, the control board monitors the coil temperature sensor for a
defrost demand. If a defrost demand exists, a defrost cycle will be
initiated at the end of the selected time interval. A defrost demand
exists when the coil temperature is at or below 32_F (0_C) for 4
minutes during the interval.
The defrost cycle is terminated when the coil temperature reaches
65_F (18_C) or 10 minutes has passed.
If the coil temperature does not reach 32_F (0_C) within the
interval, the interval timer will be reset and start over.
S Upon initial power up the first defrost interval is defaulted to 30
minutes. Remaining intervals are at selected times.
S Defrost is only allowed to occur below 50_F (10_C) outdoor
ambient temperature.
DEFROST HOLD
Defrost hold is not needed in a communicating system because the
User Interface will complete the defrost cycle before shutting down
the system.
FORCED DEFROST
Forced defrost is initiated with the User Interface.
During a Forced Defrost:
S If coil temperature is at defrost temperature of 32_F (0_C), and
outdoor air temperature is below 50_F (10_C), a full defrost
sequence will occur.
S If coil temperature or outdoor air temperature do not meet the
above requirements, an abbreviated 30 second defrost will occur.
20
Step 3 — Check for Refrigerant Leaks
Locate and repair refrigerant leaks and charge the unit as follows:
1. Use both high-- and low--pressure ports to relieve system
pressure and reclaim remaining refrigerant.
2. Repair leak following accepted practices.
NOTE: Install a filter drier whenever the system has been opened
for repair.
3. Check system for leaks using an approved method.
4. Evacuate refrigerant system and reclaim refrigerant if no
additional leaks are found.
5. Charge unit with Puron (R--410A) refrigerant, using an
accurate scale. Refer to unit rating plate for required charge.
Step 4 — Start--Up Adjustments
Complete the required procedures given in the Pre--Start--Up
section before starting the unit. Do not jumper any safety devices
when operating the unit. Do not operate the unit in cooling mode
when the outdoor temperature is below 40°F (4_C) (unless
low--ambient operation is enabled in the UI). Do not rapid cycle
the compressor. Allow 5 min. between “on” cycles to prevent
compressor damage.
CHECKING COOLING AND HEATING CONTROL
OPERATION
See UI Installation Instructions for detailed system CHECKOUT.
CHECKING AND ADJUSTING REFRIGERANT CHARGE
The refrigerant system is fully charged with Puron (R--410A)
refrigerant and is tested and factory sealed.
NOTE: Any adjustment to refrigerant charge must be done with
unit operating in HIGH stage.
NOTE:
Adjustment of the refrigerant charge is not required
unless the unit is suspected of not having the proper R--410A
charge. The charging label and the tables shown refer to system
temperatures and pressures in cooling mode only. A refrigerant
charging label is attached to the outside of the unit. If charge level
is suspect in heating mode, reclaim all refrigerant and charge to
rating plate amount. (This information may be obtained from the
physical data table also.)
IMPORTANT: When evaluating the refrigerant charge, an
indicated adjustment to the specified factory charge must always be
very minimal. If a substantial adjustment is indicated, an abnormal
condition exists somewhere in the cooling system, such as
insufficient airflow across either coil or both coils.
REFRIGERANT CHARGE
The amount of refrigerant charge is listed on the unit rating plate
and/or the physical data table. Refer to the Refrigeration Service
Techniques Manual, Refrigerants Section.
NO CHARGE
Check for leak. Use standard evacuating techniques. After
evacuating system, weigh in the specified amount of refrigerant
(refer to system rating plate).
LOW CHARGE COOLING
Use Cooling Charging Chart (Fig. 19). Vary refrigerant until the
conditions of the chart are met. Note that charging charts are
different from type normally used. Charts are based on charging
the units to correct subcooling for the various operating conditions.
Accurate pressure gauge and temperature sensing devices are
required. Connect the pressure gauge to the service port on the
suction line. Mount the temperature sensing device on the suction
line and insulate it so that the outdoor ambient does not affect the
reading. Indoor air CFM must be within the normal operating
range of the unit.
TO USE COOLING CHARGING CHARTS
Take the liquid line temperature and read the manifold pressure
gauges.
Refer to the chart to determine what the liquid line temperature
should be.
NOTE:
If the problem causing the inaccurate readings is a
refrigerant leak, refer to Check for Refrigerant Leaks section.
INDOOR AIRFLOW AND AIRFLOW ADJUSTMENTS
NOTE: Be sure that all supply-- and return--air grilles are open,
free from obstructions, and adjusted properly.
The 50XT--A unit utilizes state of the art ECM (Electronic
Computated Motor) ID Blower Motors. See UI instructions for
detailed information on adjusting airflow.
NON--COMMUNICATING EMERGENCY
COOLING /
HEATING MODE
This mode of operation is provided only in the case where the UI
has failed or is otherwise unavailable. If communications cannot be
established with the UI, the Infinity fan coil board will enable the
R, C, Y, O, and W input terminals to allow simple thermostatic
control of the 50XT--A unit.
For control with a standard thermostat, disconnect the ABCD
connectors from both control boards and using No. 18 AWG
color--coded, insulated type 90°C minimum or equivalent wire,
make the connections between the standard thermostat, the fan coil
board, and the HP/AC board per Fig. 18. Recommend the use of
interconnecting wire with 105°C, 600V, 2/64” insulation.
The Infinity control will respond to cooling and heating demands
with the maximum safe airflow based on electric heat size (if
applicable) and unit capacity.
21
50XT-- A
QUIET SHIFT
Quiet Shift is a field--selectable defrost mode which may eliminate
occasional noise that could be heard at the start of the defrost cycle
and restarting of the heating cycle. This feature must be enabled at
the UI. When activated, the following sequence of operation will
occur. Reversing valve will energize and compressor will turn off
for 30 seconds, then turn back on to complete defrost. At the end
of the defrost cycle, the reversing valve de--energizes, compressor
will turn off for another 30 seconds, and the fan will turn off for 40
seconds, before starting in the heating mode.
50XT-- A
A06297
Fig. 18 -- Non--Communicating Emergency Cooling/Heating Wiring Connections
A09109
Fig. 19 -- Cooling Charging Table--Subcooling
22
Table 3 – Wet Coil Pressure Drop (IN. W.C.)
UNIT
SIZE
24
30
36
42
48
60
600
0.005
–
–
–
–
–
700
0.007
0.007
–
–
–
–
800
0.010
0.010
–
–
–
–
900
0.012
0.012
0.019
–
–
–
1000
0.015
0.015
0.023
0.014
–
–
STANDARD CFM (SCFM)
1200
1300
1400
1500
–
–
–
–
0.021
0.024
–
–
0.032
0.037
0.042
0.047
0.020
0.024
0.027
0.031
0.027
0.032
0.036
0.041
–
–
–
0.029
1100
–
0.018
0.027
0.017
–
–
1600
–
–
–
0.035
0.046
0.032
1700
–
–
–
0.039
0.052
0.036
1800
–
–
–
0.043
0.057
0.040
1900
–
–
–
–
0.063
0.045
2000
–
–
–
–
0.068
0.049
2100
–
–
–
–
–
0.053
500
600
700
800
900
1000
1100
1200
1300
CFM
1400
1500
1600
1700
1800
1900
2000
2100
2200
2300
0.05
0.07
0.08
0.10
0.12
0.13
0.14
0.15
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
0.05
0.60
0.07
0.07
0.08
0.09
0.10
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
0.06
0.07
0.07
0.08
0.09
0.09
0.10
0.11
0.12
0.13
0.14
0.14
Table 5 – Electric Heat Pressure Drop Table (IN. W.C.)
Small Cabinet: 24--30
CFM
500
0.00
0.00
0.00
0.00
5 kw
7.2 kw
10 kw
15 kw
600
0.00
0.00
0.00
0.00
700
0.00
0.00
0.00
0.00
800
0.00
0.00
0.00
0.02
900
0.00
0.00
0.00
0.04
1000
0.00
0.00
0.02
0.06
1100
0.00
0.02
0.04
0.08
1200
0.00
0.03
0.06
0.10
1300
0.02
0.05
0.07
0.12
1400
0.04
0.07
0.09
0.14
1500
0.06
0.08
0.10
0.16
1600
0.07
0.09
0.11
0.18
Table 6 – Electric Heat Pressure Drop Table (IN. W.C.)
Large Cabinet: 36--60
1100
0.00
0.00
0.00
0.00
0.02
5kw
7.2 kw
10 kw
15 kw
20 kw
1200
0.00
0.00
0.00
0.02
0.03
1300
0.00
0.01
0.01
0.03
0.04
1400
0.01
0.02
0.02
0.04
0.05
1500
0.02
0.03
0.03
0.05
0.06
1600
0.03
0.04
0.04
0.06
0.07
1700
0.04
0.05
0.05
0.07
0.08
CFM
1800
0.05
0.06
0.06
0.08
0.09
MAINTENANCE
PERSONAL
HAZARD
AND
UNIT
2200
0.09
0.10
0.10
0.12
0.13
2300
0.10
0.11
0.11
0.13
0.14
2400
0.11
0.12
0.12
0.14
0.15
2500
0.12
0.13
0.13
0.15
0.16
WARNING
Failure to follow these warnings could result in personal
injury or death:
1. Turn off electrical power to the unit and tag before
performing any maintenance or service on this unit.
2. Use extreme caution when removing panels and parts.
3. Never place anything combustible either on or in contact
with the unit.
DAMAGE
!
Failure to follow this warning could result in personal
injury or death and possible unit component damage.
The ability to properly perform maintenance on this
equipment requires certain expertise, mechanical skills,
tools and equipment. If you do not possess these, do not
attempt to perform any maintenance on this equipment,
other than those procedures recommended in the Owner’s
Manual.
2100
0.08
0.09
0.09
0.11
0.12
ELECTRICAL SHOCK HAZARD
WARNING
INJURY
2000
0.07
0.08
0.08
0.10
0.11
!
To ensure continuing high performance, and to minimize the
possibility of premature equipment failure, periodic maintenance
must be performed on this equipment. This packaged air
conditioner unit should be inspected at least once each year by a
qualified service person. To troubleshoot unit, refer to Table 7,
Troubleshooting Chart.
NOTE TO EQUIPMENT OWNER: Consult your local dealer
about the availability of a maintenance contract.
!
1900
0.06
0.07
0.07
0.09
0.10
CAUTION
UNIT OPERATION HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
Errors made when reconnecting wires may cause improper
and dangerous operation. Label all wires prior to
disconnecting when servicing.
The minimum maintenance requirements for this equipment are as
follows:
1. Inspect air filter(s) each month. Clean or replace when
necessary.
2. Inspect indoor coil, drain pan, and condensate drain each
cooling season for cleanliness. Clean when necessary.
3. Inspect blower motor and wheel for cleanliness each
cooling season. Clean when necessary.
4. Check electrical connections for tightness and controls for
proper operation each cooling season. Service when
necessary.
23
50XT-- A
Table 4 – Filter Pressure Drop Table (IN. W.C.)
FILTER SIZE
in. (mm)
20X20X1
(508x508x25)
24X30X1
(610x762x25)
24X36X1
(610x914x25)
Step 1 — Air Filter
3. Inspect the fan blades for cracks or bends.
4. If fan needs to be removed, loosen setscrew and slide fan off
motor shaft.
5. When replacing fan blade, position blade according to the
table shown in Fig. 20.
6. Ensure that set screw engages the flat area on the motor
shaft when tightening.
7. Replace grille.
IMPORTANT: Never operate the unit without a suitable air filter
in the return--air duct system. Always replace the filter with the
same dimensional size and type as originally installed. See Table 1
for recommended filter sizes.
Inspect air filter(s) at least once each month and replace
(throwaway--type) or clean (cleanable--type) at least twice during
each cooling season and twice during the heating season, or
whenever the filter becomes clogged with dust and lint.
Step 2 — Indoor Fan and Motor (IFM)
NOTE: All motors are pre--lubricated. Do not attempt to lubricate
these motors.
For longer life, operating economy, and continuing efficiency,
clean accumulated dirt and grease from the blower wheel and
motor annually.
50XT-- A
!
Infinity Top
WARNING
A06035
UNIT SIZE
24
30
36
42
48
60
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Disconnect and install lockout tag on electrical power to the
unit before cleaning and lubricating the blower motor and
wheel.
Step 3 — Outdoor Coil, Indoor Coil, and
Condensate Drain Pan
Inspect the condenser coil, evaporator coil, and condensate drain
pan at least once each year.
The coils are easily cleaned when dry; therefore, inspect and clean
the coils either before or after each cooling season. Remove all
obstructions, including weeds and shrubs, that interfere with the
airflow through the condenser coil. Straighten bent fins with a fin
comb. If coated with dirt or lint, clean the coils with a vacuum
cleaner, using the soft brush attachment. Be careful not to bend the
fins. If coated with oil or grease, clean the coils with a mild
detergent and water solution. Rinse coils with clear water, using a
garden hose. Be careful not to splash water on motors, insulation,
wiring, or air filter(s). For best results, spray condenser coil fins
from inside to outside the unit. On units with an outer and inner
condenser coil, be sure to clean between the coils. Be sure to flush
all dirt and debris from the unit base.
Inspect the drain pan and condensate drain line when inspecting
the coils. Clean the drain pan and condensate drain by removing all
foreign matter from the pan. Flush the pan and drain trough with
clear water. Do not splash water on the insulation, motor, wiring, or
air filter(s). If the drain trough is restricted, clear it with a
“plumbers snake” or similar probe device.
Step 4 — Outdoor Fan
!
CAUTION
“A” DIM IN. (MM)
1 (26)
1 (26)
1 (26)
1 (26)
11/32 (9)
9/16 (14)
Fig. 20 -- Outdoor Fan Blade Clearance
Step 5 — Electrical Controls and Wiring
Inspect and check the electrical controls and wiring annually. Be
sure to turn off the electrical power to the unit.
Remove access panel to locate all the electrical controls and wiring.
Check all electrical connections for tightness. Tighten all screw
connections. If any smoky or burned connections are noticed,
disassemble the connection, clean all the parts, re--strip the wire
end and reassemble the connection properly and securely.
After inspecting the electrical controls and wiring, replace all the
panels. Start the unit, and observe at least one complete cooling
cycle to ensure proper operation. If discrepancies are observed in
operating cycle, or if a suspected malfunction has occurred, check
each electrical component with the proper electrical
instrumentation. Refer to the unit wiring label when making these
checks.
Step 6 — Refrigerant Circuit
Inspect all refrigerant tubing connections and the unit base for oil
accumulation annually. Detecting oil generally indicates a
refrigerant leak.
If oil is detected or if low performance is suspected, leak test all
refrigerant tubing using an electronic leak detector, or liquid--soap
solution. If a refrigerant leak is detected, refer to Check for
Refrigerant Leaks section.
If no refrigerant leaks are found and low performance is suspected,
refer to Checking and Adjusting Refrigerant Charge section.
UNIT OPERATION HAZARD
Step 7 — Indoor Airflow
Failure to follow this caution may result in damage to unit
components.
The heating and/or cooling airflow does not require checking
unless improper performance is suspected. If a problem exists, be
sure that all supply-- and return--air grilles are open and free from
obstructions, and that the air filter is clean.
Step 8 — Metering Devices--TXV & AccuRater®
Keep the condenser fan free from all obstructions to ensure
proper cooling operation. Never place articles on top of the
unit.
1. Remove 4 screws holding outdoor grille and motor to top
cover.
2. Turn motor/grille assembly upside down on top cover to
expose fan blade.
Piston
This unit uses 2 types of metering devices. The outdoor metering
device is a fixed orifice and is contained in the brass--hex body in
the liquid line feeding the outdoor coils. The indoor metering
device is a TXV--type device. No maintenance should be required.
24
Step 9 — Pressure Switches
Step 11 — Refrigerant System
Pressure switches are protective devices integrated into the control
circuit (low voltage). They shut off compressor if abnormally high
or low pressures are present in the refrigeration circuit. These
pressure switches are specifically designed to operate with Puron
(R--410A) systems. R--22 pressure switches must not be used as
replacements for the Puron (R--410A) system.
Loss--of--Charge (Low Pressure) Switch
This switch is located on the liquid line and protects against low
suction pressures caused by such events as loss of charge, low
airflow across indoor coil, dirty filters, etc. It opens if the system
pressure drops to about 20 psig. If system pressure is above this,
switch should be closed.
High--Pressure Switches (HPS & HPS2)
The high--pressure switches are located on the discharge line and
protects against excessive condenser coil pressure. HPS opens at
670 psig shutting down the compressor, while HPS2 opens at 565
psig, limiting the compressor to low--stage operation only.
High pressure may be caused by a dirty outdoor coil, failed fan
motor, or outdoor air recirculation.
To check switches:
1. Turn off all power to unit.
2. Disconnect leads on switch.
3. Apply ohm meter leads across switch. You should have
continuity on a good switch.
NOTE:
Because these switches are attached to refrigeration
system under pressure, it is not advisable to remove this device for
troubleshooting unless you are reasonably certain that a problem
exists. If switch must be removed, remove and recover all system
charge so that pressure gauges read 0 psi. Never open system
without breaking vacuum with dry nitrogen.
This step covers the refrigerant system of the 50XT--A, including
the compressor oil needed, servicing systems on roofs containing
synthetic materials, the filter drier, and refrigerant charging.
REFRIGERANT
Step 10 — Copeland Scroll Compressor (Puron
Refrigerant)
The compressor used in this product is specifically designed to
operate with Puron (R--410A) refrigerant and cannot be
interchanged.
The compressor is an electrical (as well as mechanical) device.
Exercise extreme caution when working near compressors. Power
should be shut off, if possible, for most troubleshooting techniques.
Refrigerants present additional safety hazards.
!
WARNING
EXPLOSION, FIRE HAZARD
Failure to follow this warning could result in personal
injury or death and/or property damage.
Wear safety glasses and gloves when handling refrigerants.
Keep torches and other ignition sources away from
refrigerants and oils.
The scroll compressor pumps refrigerant throughout the system by
the interaction of a stationary and an orbiting scroll. The scroll
compressor has no dynamic suction or discharge valves, and it is
more tolerant of stresses caused by debris, liquid slugging, and
flooded starts. The compressor is equipped with noise reducing
shutdown device and an internal pressure--relief port. The noise
reducing shutdown device prevents the scroll from turning
backwards and replaces the need for a cycle protector. The
pressure--relief port is a safety device, designed to protect against
extreme high pressure. The relief port has an operating range
between 550 and 625 psig differential pressure.
The Copeland scroll compressor uses Mobil 3MA POE oil.
This is the only oil allowed for oil recharge.
!
WARNING
UNIT
OPERATION,
ENVIRONMENTAL HAZARD
SAFETY
AND
This system uses Puron (R--410A) refrigerant which has
higher operating pressures than R--22 and other refrigerants.
No other refrigerant may be used in this system. Gauge set,
hoses, and recovery system must be designed to handle
Puron. If you are unsure, consult the equipment
manufacturer.
COMPRESSOR OIL
The Copeland scroll compressor uses 3MAF POE oil. If additional
oil is needed, use Uniqema RL32--3MAF. If this oil is not
available, use Copeland Ultra 32 CC or Mobil Arctic EAL22 CC.
This oil is extremely hygroscopic, meaning it absorbs water
readily. POE oils can absorb 15 times as much water as other oils
designed to HCFC and CFC refrigerants. Take all necessary
precautions to avoid exposure of the oil to the atmosphere.
SERVICING SYSTEMS ON ROOFS WITH SYNTHETIC
MATERIALS
POE (polyolester) compressor lubricants are known to cause long
term damage to some synthetic roofing materials.
Exposure, even if immediately cleaned up, may cause
embrittlement (leading to cracking) to occur in one year or more.
When performing any service that may risk exposure of
compressor oil to the roof, take appropriate precautions to protect
roofing. Procedures which risk oil leakage include, but are not
limited to, compressor replacement, repairing refrigerant leaks, and
replacing refrigerant components such as filter drier, pressure
switch, metering device, coil, accumulator, or reversing valve.
Synthetic Roof Precautionary Procedure
1. Cover extended roof working area with an impermeable
polyethylene (plastic) drip cloth or tarp. Cover an
approximate 10x10 ft (3x3 m) area.
2. Cover area in front of the unit service panel with a terry
cloth shop towel to absorb lubricant spills and prevent
run--offs, and protect drop cloth from tears caused by tools
or components.
3. Place terry cloth shop towel inside unit immediately under
component(s) to be serviced and prevent lubricant run--offs
through the louvered openings in the unit base.
4. Perform required service.
5. Remove and dispose of any oil--contaminated material per
local codes.
LIQUID--LINE BI--FLOW FILTER DRIER
The bi--flow filter drier is specifically designed to operate with
Puron. Use only factory--authorized components. Filter drier must
be replaced whenever the refrigerant system is opened. When
removing a filter drier, use a tubing cutter to cut the drier from the
system. Do not unsweat a filter drier from the system. Heat from
unsweating will release moisture and contaminants from drier into
system.
PURON (R--410A) REFRIGERANT CHARGING
Refer to unit information plate and charging chart. Some R--410A
refrigerant cylinders contain a dip tube to allow liquid
refrigerant to flow from cylinder in upright position. For
cylinders equipped with a dip tube, charge Puron units with
25
50XT-- A
Failure to follow this warning could result in personal
injury or equipment damage.
cylinder in upright position and a commercial metering device in
manifold hose. Charge refrigerant into suction line.
50XT-- A
TROUBLESHOOTING
LED DESCRIPTION
LEDs built into Infinity control boards provide installer or service
person information concerning operation and/or fault condition of
the unit controls and ECM motor. This information is also
available at the system UI in text with basic troubleshooting
instructions. Careful use of information displayed will reduce the
need for extensive manual troubleshooting. See section B and
Table 2, as well as the UI instructions, for additional information.
Additional Troubleshooting information can be found in Table 7.
MAJOR COMPONENTS
2--STAGE HP/AC BOARD
The two--stage HP/AC control board controls the following
functions:
-- Low-- and high--stage compressor operation
-- Outdoor fan motor operation
-- Reversing valve operation
-- Defrost operation
-- Low ambient cooling
-- Crankcase heater operation
-- Compressor external protection
-- Pressure switch monitoring
-- Time delay
FAN COIL BOARD
The fan coil board controls the following functions:
-- Indoor fan operation
-- Electric heat (if applicable)
SYSTEMS COMMUNICATION FAILURE
If communication with the Infinity Control is lost with the UI, the
controls will flash the appropriate fault codes. Check the wiring to
the UI, indoor and outdoor units.
MODEL PLUG
The HP/AC control board must have a valid model plug to operate.
If a valid model plug is not detected, it will not operate and the
control will flash the appropriate fault code, shown in Table 2.
PRESSURE SWITCH PROTECTION
The unit is equipped with high-- and low--pressure switches. If the
control senses the opening of a high or low pressure switch, it will
respond as follows:
1. De--energize the compressor contactor (HPS1 & LPS) or the
compressor solenoid contactor (HPS2).
2. Keep the outdoor fan operating for 15 minutes.
3. Display the appropriate fault codes.
4. After a 15 minute delay, if there is still a call for cooling and
the LPS or HPS is reset, the compressor contactor is
energized.
5. If LPS or HPS has not closed after a 15 minute delay, the
outdoor fan is turned off. If the open switch closes anytime
after the 15--minute delay, then resume operation with a call
for cooling.
6. If LPS or HPS trips 3 consecutive cycles, the unit operation
is locked out for 4 hours.
7. In the event of a high--pressure switch trip or high pressure
lockout, check the refrigerant charge, outdoor fan operation
and outdoor coil for airflow restrictions.
8. In the event of a low--pressure switch trip or low pressure
lockout, check the refrigerant charge and indoor airflow.
CONTROL FAULT
If the HP/AC control board has failed, the control will flash the
appropriate fault code (See Table 2). The control board should be
replaced.
BROWN OUT PROTECTION
If the line voltage is less than 187v for at least 4 seconds, the
appropriate compressor contactor and fan relay are de--energized.
Compressor and fan operation are not allowed until voltage is a
minimum of 190v. The control will flash the appropriate fault
code (See Table 2).
230V LINE (POWER DISCONNECT) DETECTION
If there is no 230v at the compressor contactor when the unit is
powered and cooling demand exists, the appropriate error code is
displayed. Verify that the disconnect is closed and 230v wiring is
connected to the unit.
COMPRESSOR VOLTAGE SENSING
The control board input terminals VS and L2 (See Fig. 16) are
used to detect compressor voltage status, and alert the user of
potential problems. The control continuously monitors the high
voltage on the run capacitor of the compressor motor. Voltage
should be present any time the compressor contactor is energized,
and voltage should not be present when the contactor is
de--energized.
CONTACTOR SHORTED DETECTION
If there is compressor voltage sensed when there is no demand for
compressor operation, the contactor may be stuck closed or there is
a wiring error. The control will flash the appropriate fault code.
COMPRESSOR THERMAL CUTOUT
If the control senses the compressor voltage after start--up, and is
then absent for 10 consecutive seconds while cooling demand
exists, the thermal protector is open. The control de--energizes the
compressor contactor for 15 minutes, but continues to operate the
outdoor fan. The control Status LED will flash the appropriate
code shown in Table 2. After 15 minutes, with a call for low or
high stage cooling, the compressor contactor is energized. If the
thermal protector has not re--set, the outdoor fan is turned off. If
the call for cooling continues, the control will energize the
compressor contactor every 15 minutes. If the thermal protector
closes (at the next 15 minute interval), check the unit will resume
operation.
If the thermal cutout trips for three consecutive cycles, then unit
operation is locked out for 4 hours and the appropriate fault code is
displayed.
NO 230V AT COMPRESSOR
If the compressor voltage is not sensed when the compressor
should be starting, the contactor may be stuck open or there is a
wiring error. The control will flash the appropriate fault code.
Check the contactor and control box wiring.
TROUBLESHOOTING UNIT FOR PROPER SWITCHING
BETWEEN LOW & HIGH STAGES
Check the suction pressures at the service valves. Suction pressure
should be reduced by 3--10% when switching from low to high
capacity.
NOTE: The liquid pressures are very similar between low and
high stage operation, so liquid pressure should not be used for
troubleshooting.
Compressor current should increase 20--45% when switching from
low to high stage. The compressor solenoid, when energized in
high stage, should measure 24vac.
26
If the OCT sensor should fail, low ambient cooling will not be
allowed. Defrost will occur at each time interval during heating
operation, but will terminate after 5 minutes.
If there is a thermistor out of range error, defrost will occur at each
time interval during heating operation, but will terminate after 5
minutes.
Refer to the Troubleshooting Chart (Table 7) for additional
troubleshooting information.
50XT-- A
COMPRESSOR INTERNAL RELIEF
The compressor is protected by an internal pressure relief (IPR)
which relieves discharge gas into compressor shell when
differential between suction and discharge pressures exceeds 550 -625 psig. The compressor is also protected by an internal overload
attached to motor windings.
TEMPERATURE THERMISTORS
Thermistors are electronic devices which sense temperature. As the
temperature increases, the resistance decreases. Thermistors are
used to sense outdoor ambient (OAT) and coil temperature (OCT).
Refer to Fig. 21 for resistance values versus temperature. See Fig.
22 for OCT location.
If the outdoor ambient or coil thermistor should fail, the HP/AC
control will flash the appropriate fault code (See Table 2).
IMPORTANT: Coil thermistor is factory mounted. Check to
insure thermistor is mounted properly. Outdoor air thermistor
(OAT) is field mounted and connected to two black leads (located
in the control section ) on the outdoor control board. Verify that the
OAT has been properly installed.
THERMISTOR CURVE
90
RESISTANCE (KOHMS)
80
A06311
70
Fig. 22 -- Outdoor Coil Thermistor (OCT) Attachment
60
50
FINAL CHECKS
40
30
20
10
0
0
20
40
60
80
TEMPERATURE (DEG. F)
100
120
A91431
Fig. 21 -- Resistance Values Versus Temperature
THERMISTOR SENSOR COMPARISON
The control continuously monitors and compares the outdoor air
temperature sensor and outdoor coil temperature sensor to ensure
proper operating conditions. The comparison is:
S In cooling mode, if the outdoor air sensor indicates ≥ 10 _F
(--12°C) warmer than the coil sensor (or) the outdoor air sensor
indicates ≥ 20_F (--7°C) cooler than the coil sensor, the sensors are
out of range.
S In heating if the outdoor air sensor indicates ≥ 35_F (2°C)
warmer than the coil sensor (or) the outdoor air sensor indicates
≥ 10_F (--12°C) cooler than the coil sensor, the sensors are out of
range.
IMPORTANT: Before leaving job, be sure to do the following:
1. Ensure that all wiring is routed away from tubing and sheet
metal edges to prevent rub--through or wire pinching.
2. Ensure that all wiring and tubing is secure in unit before
adding panels and covers. Securely fasten all panels and
covers.
3. Tighten service valve stem caps to 1/2--turn past finger
tight.
4. Leave Users Manual with owner. Explain system operation
and periodic maintenance requirements outlined in manual.
5. Fill out Dealer Installation Checklist and place in customer
file.
CARE AND MAINTENANCE
For continuing high performance and to minimize possible
equipment failure, periodic maintenance must be performed on this
equipment.
Frequency of maintenance may vary depending upon geographic
areas, such as coastal applications. See Users Manual for
information.
If the sensors are out of range, the control will flash the appropriate
fault code as shown in Table 2.
The thermistor comparison is not performed during low ambient
cooling operation.
FAILED THERMISTOR DEFAULT OPERATION
Factory defaults have been provided in the event of failure of
outdoor air thermistor and/or coil thermistor.
If the OAT sensor should fail, low ambient cooling will not be
allowed and the one--minute outdoor fan off delay will not occur.
Defrost will be initiated based on coil temperature and time.
27
50XT-- A
HEAT PUMP WITH PURON
REFRIGERATION SECTION QUICK--REFERENCE GUIDE
Puron refrigerant operates at 50--70 percent higher pressures than R--22. Be sure that servicing equipment and replacement components are
designed to operate with Puron. Puron refrigerant cylinders are rose colored.
S Puron refrigerant cylinders manufactured prior to March 1, 1999, have a dip tube that allows liquid to flow out of cylinder in upright
position. Cylinders manufactured March 1, 1999 and later DO NOT have a dip tube and MUST be positioned upside down to allow liquid
to flow.
S Recovery cylinder service pressure rating must be 400 psig. DOT 4BA400 or DOT BW400.
S Puron systems should be charged with liquid refrigerant. Use a commercial--type metering device in the manifold hose.
S Manifold sets should be minimum700 psig high side and 180 psig low side with 550 psig low side retard.
S Use hoses with minimum 700 psig service pressure rating.
S Leak detectors should be designed to detect HFC refrigerant.
S Puron, as with other HFCs, is only compatible with POE oils.
S Vacuum pumps will not remove moisture from oil.
S Only use factory--specified liquid--line filter driers with rated working pressures no less than 600 psig.
S Do not install a suction--line filter drier in liquid line.
S POE oils absorb moisture rapidly. Do not expose oil to atmosphere.
S POE oils may cause damage to certain plastics and roofing materials.
S Wrap all filter driers and service valves with wet cloth when brazing.
S A Puron liquid--line filter drier is required on every unit.
S Do not use an R--22 TXV.
S Never open system to atmosphere while it is under a vacuum.
S When system must be opened for service, break vacuum with dry nitrogen and replace filter driers.
S Do not vent Puron into the atmosphere.
S Observe all warnings, cautions, and bold text.
S Do not leave Puron suction line driers in place for more than 72 hrs.
28
Table 7 – Troubleshooting Chart
Compressor and outdoor fan
will not start
Compressor will not start but outdoor fan
runs
Compressor cycles (other than normally satisfying) cooling/heating calls
Compressor operates continuously
Excessive head pressure
Head pressure too low
Excessive suction pressure
Suction pressure too low
IFM does not run
IFM operation is intermittent
CAUSE
REMEDY
Power failure
Call power company
Fuse blown or circuit breaker tripped
Replace fuse or reset circuit breaker
Defective contactor, transformer, HP/AC control board,
or high--pressure, loss--of--charge or low--pressure
switch
Replace component
Insufficient line voltage
Determine cause and correct
Incorrect or faulty wiring
Check wiring diagram and rewire correctly
User Interface setting too low/too high
Reset UI setting
Units have a 5--minute time delay
DO NOT bypass this compressor time
delay–wait for 5 minutes until time--delay
relay is de--energized
Faulty wiring or circuit
Loose connections in compressor
Check wiring and repair or replace
Compressor motor burned out, seized, or
Determine cause
internal overload open
Replace compressor
Defective run capacitor, overload, or PTC (positive
temperature coefficient) thermistor
Determine cause and replace
Low input voltage
Determine cause and correct
Refrigerant overcharge or undercharge
Recover refrigerant, evacuate system, and recharge to capacities shown on rating plate
Defective compressor
Replace and determine cause
Insufficient line voltage
Determine cause and correct
Blocked outdoor coil
Determine cause and correct
Defective run/start capacitor, overload or start relay
Determine cause and replace
Faulty outdoor fan motor or capacitor
Replace
Damaged reversing valve
Determine cause and correct
Restriction in refrigerant system
Locate restriction and remove
Dirty air filter
Replace filter
Unit undersized for load
Decrease load or increase unit size
UI temperature set too low/too high
Reset UI setting
Low refrigerant charge
Locate leak, repair, and recharge
Air in system
Recover refrigerant, evacuate system, and recharge
Outdoor coil dirty or restricted
Clean coil or remove restriction
Dirty air filter
Replace filter
Dirty indoor or outdoor coil
Clean coil
Refrigerant overcharged
Recover excess refrigerant
Air in system
Recover refrigerant, evacuate system, and recharge
(Heat) Indoor air restricted or recirculating
Determine cause and correct
Indoor or outdoor air restricted or air short--cycling
Determine cause and correct
Low refrigerant charge
Check for leaks, repair and recharge
Restriction in liquid tube
Remove restriction
(Cool) High Heat load
Check for source and eliminate
Reversing valve hung up or leaking internally
Replace valve
Refrigerant overcharged
Recover excess refrigerant
(Cool) Dirty air filter
Replace filter
Low refrigerant charge
Check for leaks, repair and recharge
Metering device or low side restricted
Remove source of restriction
(Cool) Insufficient coil airflow
Increase air quantity
Check filter–replace if necessary
(Cool) Temperature too low in conditioned area
Reset UI setting
(Cool) Outdoor ambient below 55°F (13_C)
Verify low--ambient cooling enabled in UI
Filter drier restricted
Replace
Blower wheel not secured to shaft
Properly tighten blower wheel to shaft
Insufficient voltage at motor
Determine cause and correct
Power connectors not properly sealed
Connectors should snap easily; do not force
Water dripping into motor
Verify proper drip loops in connector wires
Connectors not firmly sealed
Gently pull wires individually to be sure they are
crimped into the housing
IFM-- Indoor Fan Motor
29
50XT-- A
SYMPTOM
START--UP CHECKLIST
(Remove and Store in Job Files)
I. PRELIMINARY INFORMATION
MODEL NO.:
SERIAL NO.:
DATE:
TECHNICIAN:
50XT-- A
II. PRESTART--UP (Insert check mark in box as each item is completed)
(
) VERIFY THAT ALL PACKING MATERIALS HAVE BEEN REMOVED FROM UNIT
(
) REMOVE ALL SHIPPING HOLD DOWN BOLTS AND BRACKETS PER INSTALLATION INSTRUCTIONS
(
) CHECK ALL ELECTRICAL CONNECTIONS AND TERMINALS FOR TIGHTNESS
(
) CHECK THAT INDOOR (EVAPORATOR) AIR FILTER IS CLEAN AND IN PLACE
(
) VERIFY THAT UNIT INSTALLATION IS LEVEL
(
) CHECK FAN WHEEL, AND PROPELLER FOR LOCATION IN HOUSING/ORIFICE AND SETSCREW TIGHTNESS
(
) MAKE SURE THAT -- (If Applicable) ON 60 SIZE PURON HEAT PUMP ONLY, THE TWO WIRE TIES FASTEN TO THE
OUTDOOR COILS AND REVERSING VALVE/ACCUMULATOR HAVE BEEN REMOVED
III. START--UP
ELECTRICAL
SUPPLY VOLTAGE
COMPRESSOR AMPS
INDOOR (EVAPORATOR) FAN AMPS
TEMPERATURES
OUTDOOR (CONDENSER) AIR TEMPERATURE
RETURN--AIR TEMPERATURE
COOLING SUPPLY AIR
DB
DB
WB
DB
WB
HEAT PUMP SUPPLY AIR __________________
ELECTRIC HEAT SUPPLY AIR_______________
PRESSURES
REFRIGERANT SUCTION
PSIG, SUCTION LINE TEMP*
REFRIGERANT DISCHARGE
PSIG, LIQUID TEMP{
(
) VERIFY REFRIGERANT CHARGE USING CHARGING CHARTS
(
) TEMPERATURE RISE (See Literature) RANGE _______________
(
) MEASURED TEMPERATURE RISE ____________
* Measured at suction inlet to compressor
{ Measured at liquid line leaving condenser.
Copyright 2012 Carrier Corp. D 7310 W. Morris St. D Indianapolis, IN 46231
Edition Date: 06/12
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
30
Catalog No:50XT ---06SI
Replaces: 50XT--- 05SI