RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
IMPORTANT
The Clean Air Act of 1990 bans the intentional venting of
refrigerant (CFCs, HCFCs AND HFCs) as of July 1,
1992. Approved methods of recovery, recycling or
reclaiming must be followed. Fines and/or incarceration
may be levied for noncompliance.
WARNING
This product and/or the indoor unit it is matched with may
contain fiberglass wool.
Disturbing the insulation during installation,
maintenance, or repair will expose you to fiberglass wool
dust. Breathing this may cause lung cancer. (Fiberglass
wool is known to the State of California to cause cancer.)
Fiberglass wool may also cause respiratory, skin, and
eye irritation.
To reduce exposure to this substance or for further
information, consult material safety data sheets.
INSTALLATION
INSTRUCTIONS
T-CLASSt TPA Series
7.5 AND 10 TON
HEAT PUMPS
7.5 TO 10 TONS
506148-01
12/2015
Supersedes 10/2011
Table of Contents
Shipping and Packing List 1......................
Outdoor Unit 1..................................
Unit Dimensions, Corner Weights and Center of
Gravities 2.....................................
Unit Plumbing Parts Arrangement 3...............
Unit Control Box Components Arrangement 4.......
Model Number Identification 4....................
Rigging the Unit for Lifting 4......................
Installation Clearances 5.........................
Line Set 5......................................
Refrigerant Charge and Check 8..................
System Operation 11.............................
Defrost System 11...............................
Defrost Control Board 11..........................
Maintenance 12..................................
Start-up and Performance Checklist 13.............
Shipping and Packing List
Check the unit for shipping damage and listed times below
are intact. If damaged, or if parts are missing, immediately
contact the last shipping carrier.
1 — Assembled outdoor unit
1 — Installation instruction
Outdoor Unit
Litho U.S.A.
WARNING
Improper installation, adjustment, alteration, service or
maintenance can cause personal injury, loss of life, or
damage to property.
Installation and service must be performed by a licensed
professional installer (or equivalent) or a service agency.
TPA series heat pumps, which will also be referred to in this
instruction as the outdoor unit, uses HFC-410A
refrigerant. This outdoor unit must be installed with a
matching indoor unit and line set as outlined in the TP
Engineering Handbook.
This outdoor unit is designed for use in thermal expansion
valve (TXV) systems only.
Unit Dimensions, Corner Weights and Center of Gravities
Corner Weights
Model No.
TPA090S4S 105 48 105 48 112 51 112 51
TPA120S4S 129 59 11 0 50 123 56 145 66
5
(127)
AA BB CC DD
lbs. kg lbs. kg lbs. kg lbs. kg
9−1/8
(232)
1−1/8
(29)
1−1/8
(29)
LIQUID
LINE
SUCTION
LINE
Model No.
TPA090S4S 21.75 552 29.0 737
TPA120S4S 20.0 508 28.25 718
OUTDOOR
FAN GUARDS
CENTER OF
GRAVITY
FF
Center of Gravities
EE FF
inch mm inch mm
OPTIONAL HAIL GUARD
(Field Installed All Coil Sides)
(Not used with Coil Guard)
INLET AIR
BBAA
EE
INLET AIR
2−1/2
(54)
REFRIGERANT LINE
CONNECTIONS DETAIL
OPTIONAL COIL GUARD
(Field Installed All Coil Sides)
(Not used with Hail Guard)
57−7/8
(1470)
DISCHARGE
COMPRESSOR
FORKLIFT SLOTS
(Both Sides)
FRONT VIEW
AIR
60−1/8
(1527)
BASE
ELECTRICAL
INLETS (Above
Refrigerant Lines)
OPTIONAL HAIL GUARD
(Field Installed All Coil Sides)
(Not used with Coil Guard)
CONTROL
BOX ACCESS
REFRIGERANT
LINE CONNECTIONS
SEE DETAIL
ELECTRICAL
INLETS (Above
Refrigerant Lines)
DD
TOP VIEW
DISCHARGE
AIR
LIFTING HOLES
(For Rigging)
SIDE VIEW
41−3/8
(1051)
43−5/8
(1108)
CC
OPTIONAL
INLET AIR
BASE
(Field Installed All Coil Sides)
(Not used with Hail Guard)
COIL GUARD
(Field Installed
All Coil Sides)
(Not used with
Hail Guard)
(286)
2 (51)
OPTIONAL
COIL GUARD
12
48−3/4
(1238)
45−1/4
(1149)
3−1/2
(89)
Page 2
Unit Plumbing Parts Arrangement
TPA090S4S
REVERSING
VALV E
HIGH PRESSURE
SWITCH (S4)
CHECK EXPANSIVE VALVE
(CTXV)
LOSS-OF-CHARGE
SWITCH (S24)
COIL
DEFROST SWITCH
LOCATION (S6)
TPA120S4S
DEFROST SWITCH
LOCATION (S9)
COMPRESSOR
LIQUID LINE BI-FLOW DRIER
HIGH PRESSURE
SWITCH (S4)
REVERSING
VALV E
SUCTION LINE SERVICE
VALV E
LIQUID LINE SERVICE
VALV E
CTXV SENSING BULB
DEFROST SWITCH
LOCATION (S6)
CTXV SENSING BULB
COMPRESSOR
LIQUID LINE BI-FLOW DRIER
Page 3
LIQUID LINE SERVICE
VALV E
COIL
CTXV SENSING BULB
LOSS OF CHARGE SWITCH
(S24)
SUCTION LINE SERVICE
VALV E
TP SERIES
Unit Control Box Components Arrangement
TPA090S4S AND TPA120S4S
TRANSFORMER
CONTACTOR (K1)
RUN CAPACITORS
Model Number Identification
T = T-Class™ Product Line
Brand/Family
P = Split System Heat Pump
Major Design Sequence
Unit Type
A = 1st Generation
B = 2nd Generation
Nominal Cooling Capacity -
(T1)
(C1, C2,)
TPA Y1120 S N4 S
Tons
090 = 7.5 Tons
120 = 10 Tons
DEFROST CONTROL
BOARD
RELAY (K149)
TERMINAL STRIP (TB14)
RELAY (K10)
GROUND LUG
Vol t ag e
Y = 208/230V‐3 phase‐60hz
G = 460V‐3 phase‐60hz
J = 575V‐3 phase‐60hz
Minor Design Sequence
1 = 1st Revision
2 = 2nd Revision
3 = 3rd Revision
Part Load Capability
N = Single Stage Compressor
Refrigerant Circuits
S = Single Circuit
Rigging the Unit for Lifting
Rig the unit for lifting by attaching four cables to the holes in
the base rail of the unit as illustrated in figure 5.
1. Remove protective packaging before rigging the unit
for lifting.
Page 4
Refrigerant Type
4 = R-410A
Cooling Efficiency
S = Standard Efficiency
2. Connect the rigging to the holes in each corner of the
unit's base.
3. All panels must be in place for rigging.
4. Place a field‐provided H‐style frame just above the
top edge of the unit. The frame must be of adequate
strength and length. (An H‐style frame will prevent
the top of the unit from being damaged.)
Lifting point should be directly above the center of gravity.
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
ППППППППППППППП
Line Set
Caution - do not
walk on unit.
Important - all panels
must be in place for
rigging.
Figure 1. TPA 090S4S and TPA 120S4S
Installation Clearances
See Unit Dimensions on page to sizing mounting slab,
platforms or supports. Refer to figure 2 for mandatory
installation clearance requirements.
NOTES:
Field refrigerant piping consists of liquid and suction lines
connecting the condensing unit and the indoor unit. Liquid
and suction service valves are located in a compartment at
the corner of the unit below the control box. Piping can be
routed directly from the service valves or field supplied
elbows can be added to divert the piping as required
Refer to table 1 for field-fabricated refrigerant line sizes for
runs up to 50 linear feet (15 m).
Table 1. Refrigerant Line Sizes for Runs
Up to 50 Linear Feet
Unit Liquid Line Suction Line
TPA 090 5/8” (16 mm) 1-3/8” (35 mm)
TPA 120 5/8” (16 mm) 1-3/8” (35 mm)
Refrigerant Line Limitations
You may install the unit in applications that have line set
lengths of up to 50 linear feet (15 m) with refrigerant line
sizes as outlined in table 1 (excluding equivalent length of
fittings). Size refrigerant lines greater than 50 linear feet
(15m or greater) according to the Lennox Refrigerant
Piping Design and Fabrication Guidelines (Corp. 9351-L9)
or latest version.
Clearance to one of the remaining two sides may be
12 in. (305 mm) and the final side may be 6 in. (152
mm).
A clearance of 24 in. (610 mm) must be maintained
between two units.
48 in. (1219 mm) clearance required on top of unit.
SEE
NOTES
SEE
NOTES
*One of these clearance distances may be reduced to 18 inches (457 mm).
**This clearance may be reduced to 12 inches (305 mm).
Note- 48 in. (1219 mm) clearance required above top of unit.
Figure 2. TPA 090S4S and TPA 120S4S
Installation Clearances
36 (914)
30
(762)
Electrical Connections
WARNING
Electric Shock Hazard. Can cause injury
or death.
Line voltage is present at all components
on units with single‐pole contactors, even
when unit is not in operation!
Unit may have multiple power supplies.
Disconnect all remote electric power
supplies before opening access panel.
Unit must be grounded in accordance
with national and local codes.
In the United States, wiring must conform with current local
codes and the current National Electric Code (NEC). In
Canada, wiring must conform with current local codes and
the current Canadian Electrical Code (CEC).
TRANSFORMER - 24VAC, 70VA - PROVIDED
NOTE — The addition of accessories to the system could
exceed the 70VA power requirement of the
factory‐provided transformer. Measure the system's
current and voltage after installation is complete to
determine transformer loading. If loading exceeds the
factory‐provided transformer capacity, a larger
field‐provided transformer will need to be installed in the
system.
Page 5
TP SERIES
CIRCUIT SIZING AND DISCONNECT SWITCH
1
MAIN FUSE
BOX/BREAKER
PANEL
DISCONNECT
SWITCH
TYPICAL HIGH VOLTAGE POWER SUPPLY
2
CONNECTIONS
CONTROL BOX
USE THE LEFT CUTOUT TO ROUTE
HIGH VOLTAGE WIRING TO THE K1
CONTACTOR ON THE TPA 090S AND
120S MODELS.
K1 CONTACTOR
GROUND LUG
LEFT CUTOUT
NOTE — ANY EXCESS HIGH VOLTAGE
FIELD WIRING SHOULD BE TRIMMED
AND SECURED AWAY FROM ANY LOW
VOLTAGE FIELD WIRING.
Refer to the unit nameplate for minimum circuit ampacity amperage
minimum, and maximum fuse or circuit breaker fusible (HACR per
NEC). Install power wiring and properly sized disconnect switch.
NOTE — UNITS ARE APPROVED FOR USE ONLY WITH COPPER CONDUCTORS.
GROUND UNIT AT DISCONNECT SWITCH OR TO AN EARTH GROUND.
INSTALL THERMOSTAT
3
THERMOSTAT
5 FEET
(1.5M)
Install room thermostat (ordered separately) on an inside wall
approximately in the center of the conditioned area and 5 feet (1.5m)
from the floor. It should not be installed on an outside wall or where it
can be affected by sunlight, drafts or vibrations.
HIGH VOLTAGE WIRING
CONNECT EARTH GROUND TO
GROUND LUG
TYPICAL CONTROL WIRING
4
TPA HEAT
PUMP
R
C1
W1
W2
C
TAA AIR
HANDER
RO
C1
W1
W2
C
A2
THERMOSTAT
R
S1
S2
Y1
W
W2
C
Install low voltage wiring from outdoor to indoor unit and from
thermostat to indoor unit as illustrated.
RT2 REMOTE
SENSOR
TYPICAL UNIT LOW VOLTAGE CONNECTIONS
5
K1 CONTACTOR
HIGH VOLTAGE WIRING
EARTH GROUND CONNECTION
CONTROL BOX
ROUTE THROUGH WIRE TIES
B
TIGHTEN WIRE TIES
D
RIGHT CUTOUT
A
WIRE NUTS
LOW VOLTAGE CONTROL
C
WIRING
Page 6
WIRE RUN LENGTH AWG# INSULATION TYPE
LESS THAN 100' (30 METERS) 18 TEMPERATURE RATING
MORE THAN 100' (30 METERS) 16 35ºC MINIMUM.
A Run control wires through right cutout.
B Run control wires through wire ties.
C Make control wire connections using field
provided wire nuts. See figure 3 for
connections requirements.
D Tighten wire tie to secure 24V low voltage
control wiring.
NOTE — FOR PROPER VOLTAGES, SELECT THERMOSTAT WIRE (CONTROL
WIRES) GAUGE PER TABLE ABOVE.
NOTE — WIRE TIE PROVIDES LOW VOLTAGE WIRE STRAIN RELIEF AND TO MAINTAIN
SEPARATION OF FIELD INSTALLED LOW AND HIGH VOLTAGE CIRCUITS.
NOTE — DO NOT BUNDLE ANY EXCESS 24VAC CONTROL WIRES INSIDE
CONTROL BOX.
Figure 3. TPA090S4S and TPA120S4S G, J, M, and Y Voltages) Typical Wiring Diagram
Page 7
TP SERIES
Refrigerant Charge and Check
TPA units have a factory holding charge of 1 pound of
HFC-410A. Additional refrigerant will need to be added
during installation (table 2).
Table 2. Adding Refrigerant
Models
TPA090 /
TAA090
TPA120 /
TAA120
(2) TPA090 /
TAA240
1
Total amount of charge necessary to accommodate 25
25 Feet
(pounds)
17 5/8 1-3/8 1.8
23 5/8 1-3/8 1.8
3
23
Line
Diameter
(inches)
5/8 1-3/8 1.8
Liquid
1
Vapor
Line
Diameter
(inches)
feet of line set.
2
If line set length is greater than 25 feet, add this amount to
each circuit. If line set is less than 25 feet, subtract this
amount from each circuit. Refer to Lennox Refrigerant
Piping Design and Fabrication Guidelines for more
information.
3
Charge amount per outdoor unit.
NOTE - Refrigerant line sets longer than 200 feet (60 meters)
are not recommended. For assistance contact Lennox
Application Department.
To charge the system, use either of the following
procedures:
CHARGE PROCEDURE — NORMAL OPERATING
PRESSURES
1. Connect a manifold gauge set to the service valves:
A Low pressure gauge to vapor service port.
B High pressure gauge to liquid valve service port
2. Operate system in cooling mode until pressures and
temperatures stabilize (5 minutes minimum).
3. Use a thermometer to measure the outdoor ambient
temperature. The outdoor temperature will determine
which charging procedure to use.
Outdoor Temp > 65ºF (18ºC)
1. Apply the outdoor ambient temperature to tables 4 or
5 to determine normal operating pressures. Compare
the normal operating pressures to the pressures
obtained from the connected gauges. If discharge
pressure is high, remove refrigerant from the system.
If discharge pressure is low, add refrigerant to the
system.
A Add or remove charge in increments.
B Allow the system to stabilize at least 5 minutes
each time refrigerant is added or removed
2. Minor variations in these pressures may be expected
due to differences in installations. Significant differences
could mean that the system is not properly charged or
that a problem exists with some component in the
system.
3. Switch to heating mode to confirm normal operating
pressures. Let the system stabilize at least 10 minutes
Adjustment
per foot of
2
Line
(Ounces)
then compare the pressure obtained from the
connected gauges to the normal operating pressures
(heating mode) in table 5.
4. Verify the charge, as described in the approach
method section.
Outdoor Temp < 65ºF (18ºC)
1. When the outdoor ambient temperature is below 65F
(18C) it may be necessary to restrict the air flow
through the outdoor coil to achieve liquid pressures in
the 325-375 psig (2240-2585 kPa) range. These
higher pressures are necessary for checking the
charge. Block equal sections of the outdoor coil on all
coil sides until the liquid pressure is in the 325-375 psig
range (figure 4).
2. Charge the system as described in the approach
method section.
3. Switch to heating mode and let the system stabilize at
least 10 minutes. Then confirm that the pressures
obtained from the connected gauges match the
normal operating pressures (heating mode) in table 5
4. Minor variations in these pressures may be expected
due to differences in installations. Significant
differences could mean that the system is not properly
charged or that a problem exists with some
component in the system.
CARDBOARD OR
PLASTIC SHEET
OUTDOOR COIL SHOULD BE BLOCKED ONE SIDE AT A TIME
WITH CARDBOARD OR PLASTIC SHEET UNTIL PROPER
TESTING PRESSURES ARE REACHED.
Figure 4. Blocking Outdoor Coil
PROCEDURE — APPROACH METHOD
Use the following approach method along with the normal
operating pressures in cooling mode to confirm readings.
1. Using the same thermometer, compare liquid
temperature at service valve to outdoor ambient
temperature.
Approach Temperature = Liquid temperature
minus ambient temperature
2. Approach temperature should be as indicated in table
3 for each stage. An approach temperature greater
then this value indicates an undercharge. An approach
temperature less than this value indicates an
overcharge.
A Add or remove charge in increments.
B Allow the system to stabilize at least 5 minutes
each time refrigerant is added or removed
Page 8
Table 3. HFC-410A Approach Temperatures
TPA090 / TAA090
TPA120 / TAA120
TPA090 / TAA090
TPA120 / TAA120
Approach
Models
TPA090S4S /
TAA090
TPA120S4S /
TAA120
(2) TPA090S4S
/ TAA240
Stage
1, 2 8.0 4.4
Temperature (F)
(+/- 1)
1 7.0 3.8
1 8.0 4.4
Approach
Temperature (C)
(+/- 0.5)
3. Do not use the approach method if system pressures
do not match pressures in tables 4 or 5 except when
the outdoor ambient temperature is below 65
(18ºC).
The approach method is not valid for grossly
over or undercharged systems.
Table 4. HFC-410A Normal Operating Pressures — Cooling Mode (Liquid +10 and Suction +5 psig)
(2) TPA090 / TAA240
Temp*
Liquid Suction Liquid Suction Liquid Suction Liquid Suction
65 F (18 C)
75 F (24 C)
85 F (29 C)
95 F (35 C)
105 F (41 C)
115 F (46 C)
125 F (52 C)
231 128 243 130 239 132 239 132
265 130 281 133 289 135 289 135
310 131 325 136 322 137 322 137
358 134 372 139 370 140 370 140
410 137 427 140 422 142 422 142
467 140 478 142 480 145 480 145
551 146 548 142 541 148 541 148
*Temperature of air entering outdoor Coil
Stage 1 Stage 2
ºF
Table 5. HFC-410A Normal Operating Pressures — Heating Mode (Liquid +10 and Suction +5 psig)
(2) TPA090 / TAA240
Temp*
Liquid Suction Liquid Suction Liquid Suction Liquid Suction
60 F (15 C)
50 F (10 C)
47 F (8 C)
40 F (4 C)
30 F (-1 C)
20 F (-6 C)
17 F (-8 C)
384 116 367 120 394 117 394 117
366 101 350 105 376 102 376 102
361 96 345 101 370 97 370 97
348 85 333 91 357 87 357 87
330 70 316 76 338 72 338 72
312 55 299 61 320 57 320 57
307 50 294 57 314 52 314 52
*Temperature of air entering outdoor Coil
Stage 1 Stage 2
Page 9
TP SERIES
Table 6. HFC-410A Temperature (°F) - Pressure (Psig)
°F Psig °F Psig °F Psig °F Psig °F Psig °F Psig °F Psig °F Psig
32 100.8 48 137.1 63 178.5 79 231.6 94 290.8 110 365.0
33 102.9 49 139.6 64 181.6 80 235.3 95 295.1 111 370.0 126 451.8 142 552.3
34 105.0 50 142.2 65 184.3 81 239.0 96 299.4 112 375.1 127 457.6 143 559.1
35 107.1 51 144.8 66 187.7 82 242.7 97 303.8 113 380.2 128 463.5 144 565.9
36 109.2 52 147.4 67 190.9 83 246.5 98 308.2 114 385.4 129 469.5 145 572.8
37 111.4 53 150.1 68 194.1 84 250.3 99 312.7 115 390.7 130 475.6 146 579.8
38 113.6 54 152.8 69 197.3 85 254.1 100 317.2 11 6 396.0 131 481.6 147 586.8
39 115.8 55 155.5 70 200.6 86 258.0 101 321.8 11 7 401.3 132 487.8 148 593.8
40 118.0 56 158.2 71 203.9 87 262.0 102 326.4 11 8 406.7 133 494.0 149 601.0
41 120.3 57 161.0 72 207.2 88 266.0 103 331.0 11 9 412.2 134 500.2 150 608.1
42 122.6 58 163.9 73 210.6 89 270.0 104 335.7 120 417.7 135 506.5 151 615.4
43 125.0 59 166.7 74 214.0 90 274.1 105 340.5 121 423.2 136 512.9 152 622.7
44 127.3 60 169.6 75 217.4 91 278.2 106 345.3 122 428.8 137 519.3 153 630.1
45 129.7 61 172.6 76 220.9 92 282.3 107 350.1 123 434.5 138 525.8 154 637.5
46 132.2 62 175.4 77 224.4 93 286.5 108 355.0 124 440.2 139 532.4 155 645.0
47 134.6 78 228.0 109 360.0 140 539.0
125 445.9
141 545.6
Page 10
System Operation
The outdoor unit and indoor blower cycle on demand from
the room thermostat. When the thermostat blower switch
is in the ON position, the indoor blower operates
continuously.
HIGH PRESSURE SWITCHES (S4 AND S7)
These units are equipped with a auto‐reset high pressure
switch (single-pole, single-throw) which is located on the
discharge line. The switch shuts off the compressor when
discharge pressure rises above the factory setting. High
Pressure (auto reset) - trip at 640 psig, reset at 512 psig.
LOSS-OF-CHARGE SWITCH (S24)
These units are equipped with a loss-of-charge switch that
is located on the liquid line. The switch is a SPST,
auto-reset switch that is normally closed. The switch
opens at 40 psi and closes at 90 psi.
Defrost System
The defrost system includes a defrost thermostat and a
defrost control.
DEFROST THERMOSTAT
The defrost thermostat is located on the liquid line between
the check/expansion valve and the distributor on each coil.
When the defrost thermostat senses 42°F (5.5°C) or
cooler, its contacts close and send a signal to the defrost
control board to start the defrost timing. It also terminates
defrost when the liquid line warms up to 70°F (21°C).
DEFROST CONTROL
The defrost control board includes the combined functions
of a time/temperature defrost control, defrost relay, time
delay, diagnostic LEDs, and a terminal strip for field wiring
connections.
The control provides automatic switching from normal
heating operation to defrost mode and back. During
compressor cycle (defrost thermostat is closed, calling for
defrost), the control accumulates compressor run times at
30, 60, or 90 minute field adjustable intervals. If the defrost
thermostat is closed when the selected compressor run
time interval ends, the defrost relay is energized and
defrost begins.
Each timing pin selection provides a different accumulated
compressor run time period for one defrost cycle. This time
period must occur before a defrost cycle is initiated. The
defrost interval can be adjusted to 30 (T1), 60 (T2), or 90
(T3) minutes. The maximum defrost period is 14 minutes
and cannot be adjusted.
NOTE — Defrost control part number is listed near the P1
timing pins.
Units with defrost control 100269-02: The factory
default defrost interval is 60 minutes.
Units with defrost control 100269-04 or higher: The
factory default defrost interval is 90 minutes.
If the timing selector jumper is missing, the defrost control
defaults to a 90-minute defrost interval.
Defrost Control Board
DEFROST CONTROL TIMING PINS
FIELD SELECT
TIMING PINS
TEST
PINS
DIAGNOSTIC
COMPRESSOR
DELAY PINS
REVERSING
VALV E
S24
LOSS-OF-CHARGE
HIGH PRESSURE
SWITCH
DEFROST
THERMOSTAT
S4
SWITCH
Figure 5. Outdoor Unit Defrost Control Board
A TEST option is provided for troubleshooting. The TEST
mode may be started any time the unit is operating in
the heating mode and the defrost thermostat is closed
or jumpered. If the jumper is in the TEST position at
power‐up, the control will ignore the test pins. When the
jumper is placed across the TEST pins for two seconds,
the control will enter the defrost mode. If the jumper is
removed before an additional 5-second period has
elapsed (7 seconds total), the unit will remain in defrost
mode until the defrost thermostat opens or 14 minutes
have passed. If the jumper is not removed until after the
additional 5-second period has elapsed, the defrost will
terminate and the test option will not function again until the
jumper is removed and re-applied.
COMPRESSOR DELAY
The defrost board has a field-selectable function to reduce
occasional sounds that may occur while the unit is cycling
in and out of the defrost mode. When the compressor
delay jumper is removed, the compressor will be cycled off
for 30 seconds going in and out of the defrost mode.
NOTE — The 30‐second compressor feature is ignored
when the TEST pins have been jumpered.
TIME DELAY
The timed-off delay is five minutes long. The delay helps
protect the compressor from short-cycling in case the
power to the unit is interrupted or a pressure switch opens.
The delay is bypassed by placing the timer select jumper
across the TEST pins for 0.5 seconds.
NOTE — The board must have a thermostat demand for
the bypass function.
LEDS
24V TERMINAL
STRIP
CONNECTIONS
SERVICE LIGHT
CONNECTIONS
Page 11
TP SERIES
PRESSURE SWITCH CIRCUITS
The defrost control includes two pressure switch circuits.
The factory-installed high pressure switch (S4) wires are
connected to the board's HI PS terminals (figure 5). The
board also includes LO PS terminals to accommodate the
factory installed loss-of-charge switch.
During a single thermostat cycle, the defrost control will
lock out the unit after the fifth time that the circuit is
interrupted by any pressure switch that is wired to the
control board. In addition, the diagnostic LEDs will indicate
a pressure switch lockout after the fifth occurrence of an
open pressure switch (table 7). The unit will remain locked
out until power is broken then remade to the control or until
the jumper is applied to the TEST pins for 0.5 seconds.
NOTE — The defrost control board ignores input from the
loss-of-charge switch terminals during the TEST mode,
during the defrost cycle, during the 90-second start-up
period, and for the first 90 seconds each time the reversing
valve switches heat/cool modes. If the TEST pins are
jumpered and the 5-minute delay is being bypassed,
the LO PS terminal signal is not ignored during the
90-second start-up period.
SERVICE LIGHT CONNECTION
The defrost control board includes terminal connections
for a service light which provides a signal that activates the
room thermostat service light during periods of inefficient
operation.
IMPORTANT
After testing has been completed, properly reposition
test jumper across desired timing pins.
DIAGNOSTIC LEDS
The defrost board uses two LEDs for diagnostics. The
LEDs flash a specific sequence according to the diagnosis
(table 7).
Table 7. Defrost Control Board Diagnostic LEDs
DS2 Green DS1 Red Condition
OFF OFF Power problem
Simultaneous Slow Flash Normal operation
Alternating Slow Flash 5-min. anti-short cycle delay
Fault and Lockout Codes
OFF Slow Flash Loss-of-Charge Fault
OFF ON Loss-of-Charge Lockout
Slow Flash OFF High Pressure Fault
ON OFF High Pressure Lockout
Maintenance
At the beginning of each cooling season, the system
should be checked as follows:
OUTDOOR UNIT
1. Clean and inspect the condenser coil. You can flush
the coil with a water hose.
2. The outdoor fan motor is prelubricated and sealed. No
further lubrication is necessary.
3. Visually inspect connecting lines and coils for
evidence of oil leaks.
4. Check wiring for loose connections.
5. Check for correct voltage at the unit while the unit is
operating and while it is off.
6. Check amp-draw of the outdoor fan motor.
Unit Nameplate _________ Actual ____________
7. Check amp-draw of the compressor.
Unit Nameplate _________ Actual ____________
NOTE - If the owner complains of insufficient cooling,
gauge the unit and check the refrigerant charge. Refer to
section on refrigerant charging in this instruction.
INDOOR COIL
1. If necessary, clean the coil.
2. Check connecting lines and coils for evidence of oil
leaks.
3. If necessary, check the condensate line and clean it.
INDOOR UNIT
1. Clean or change filters.
2. Adjust the blower speed for cooling. Measure the
pressure drop over the coil to determine the correct
blower CFM. Refer to the unit information service
manual for pressure drop tables and procedure.
3. On belt drive blowers, check the belt for wear and
proper tension.
4. Check all wiring for loose connections.
5. Check for correct voltage at the unit (blower
operating).
6. Check amp-draw on blower motor.
Unit Nameplate _________ Actual ____________
WARNING
Electric shock hazard. Can cause injury or
death. Before attempting to perform any
service or maintenance, turn the electrical
power to unit OFF at disconnect
switch(es). Unit may have multiple power
supplies.
Page 12
Start-Up and Performance Checklist
Job Name Job no. Date
Job Location City State
Installer City State
Unit Model No. Serial No. Service Technician
Nameplate Voltage
Rated Load Ampacity Compressor Amperage:
Maximum Fuse or Circuit Breaker
Electrical Connections Tight? Indoor Filter clean? Supply Voltage (Unit Off)
Indoor Blower RPM S.P. Drop Over Indoor (Dry) Outdoor Coil Entering Air Temp.
Vapor Pressure;
Refrigerant Lines: Leak Checked? Properly Insulated? Outdoor Fan Checked?
Service Valves: Fully Opened? Caps Tight? Voltage With Compressor Operating
SEQUENCE OF OPERATION
Heating Correct? Cooling Correct?
Calibrated?
THERMOSTAT
Properly Set? Level?
Page 13
TP SERIES
Loading...