Lennox International Inc Heat Pump 4HP18LT User Manual

INSTALLATION AND MAINTENANCE INSTRUCTIONS  
4HP18LT Series  
Split System Heat Pump  
Save these instructions for future reference  
WARNING  
The equipment covered in this manual is to be installed by trained and experienced service  
and installation technicians. Improper installation, modification, service, or use can cause  
electrical shock, fire, explosion, or other conditions which may cause personal injury, death,  
or property damage. Use appropriate safety gear including safety glasses and gloves  
when installing this equipment.  
WARNING  
TABLE OF CONTENTS  
Risk of electrical shock. Disconnect all remote power  
supplies before installing or servicing any portion of the  
INSTALLATION ....................................................2  
system. Failure to disconnect power supplies can result  
in property damage, personal injury, or death.  
CONNECTION DIAGRAM....................................4  
START-UP ..........................................................13  
OPERATION ......................................................18  
WARNING  
MAINTENANCE .................................................23  
Installation and servicing of air conditioning equipment  
can be hazardous due to internal refrigerant pressure  
and live electrical components. Only trained and qualified  
service personnel should install or service this equipment.  
Installation and service performed by unqualified persons  
Manufactured By  
can result in property damage, personal injury, or death.  
Allied Air Enterprises, Inc.  
A Lennox International Inc. Company  
215 Metropolitan Drive  
West Columbia, SC 29170  
WARNING  
Sharp metal edges can cause injury. When installing  
the unit, use care to avoid sharp edges.  
*506470-01*  
506470-01  
Issue 1007  
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Install the unit high enough above the ground or roof to  
allow adequate drainage of defrost water and prevent  
ice buildup.  
If unit coil cannot be mounted away from prevailing winter  
winds, a wind barrier should be constructed (See Figure 3).  
Size the barrier at least the same height and width as the  
outdoor unit. Mount barrier 24” from the sides of the unit in  
the direction of the prevailing winds.  
In heavy snow areas, do not locate the unit where drifting  
snow will occur. The unit base should be elevated above  
the depth of average snows.  
NOTE: Elevation of the unit may be accomplished by  
construction a frame using suitable materials. If a  
support frame is constructed, it must not block drain  
holes in unit base.  
When installed in areas where low ambient temperatures  
exist, locate unit so winter prevailing winds do not blow  
directly into outdoor coil.  
Locate unit away from overhanging roof lines which  
would allow water or ice to drop on, or in front of, coil or  
into unit.  
Figure 3  
Slab Mounting  
When installing a unit at grade level, install on slab high  
enough above grade so that water from higher ground will  
not collect around the unit (See Figure 2). Slab should have  
a slope tolerance away from the building of 2° or 2” per 5’.  
This will prevent ice from building up under the unit during a  
defrost cycle. Refer to following roof mounting section for  
barrier construction if unit must face prevailing winter winds.  
Electrical Wiring  
All field wiring must be done in accordance with the National  
Electrical Code (NEC) recommendations, Canadian  
Electrical Code (CEC) and CSA Standards, or local codes,  
where applicable.  
Refer to the furnace or blower coil installation instructions  
for additional wiring application diagrams and refer to unit  
rating plate for minimum circuit ampacity and maximum  
overcurrent protection size.  
Slab Mounting  
Discharge Air  
Building  
Structure  
WARNING  
Unit must be grounded in accordance with national and  
local codes. Failure to ground unit properly can result in  
personal injury or death.  
Mounting Slab  
Ground Level  
WARNING  
Figure 2  
Line voltage is present at all components when unit is  
not in operation on units with single pole contactors.  
Disconnect all remote electric power supplies before  
opening access panel. Unit may have multiple power  
supplies. Failure to disconnect all power supplies could  
result in personal injury or death.  
Roof Mounting  
Install unit at a minimum of 6” above surface of the roof to  
avoid ice buildup around the unit. Locate the unit above a  
load bearing wall or area of the roof that can adequately  
support the unit. Consult local codes for rooftop applications.  
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Page 3  
Refrigerant Piping  
If the 4HP18LT unit is being installed with a new indoor coil  
and line set, the refrigerant connections should be made as  
outlined in this section. If an existing line set and/or indoor  
coil will be used to complete the system, refer to this section  
as well as the section that follows entitled - Flushing  
Existing Line Set and Indoor Coil.  
If this unit is being matched with an approved line set or  
indoor coil which was previously charged with R-22  
refrigerant, the line set and coil must be flushed prior to  
installation. If the unit is being used with and existing indoor  
coil which was equipped with a liquid line which served as a  
metering device (RFCI), the liquid line must be replaced prior  
to the installation of the 4HP18LT unit.  
Field refrigerant piping consists of liquid and suction lines  
from the outdoor unit (sweat connections) to the indoor coil  
(flare or sweat connections).  
Select line set diameters from Table 2 to ensure that oil  
returns to the compressor. Size vertical suction riser to  
maintain minimum velocity at minimum capacity.  
Recommended line length is 50’ or less. If more than 50’  
line set is required, contact Technical Services. Table 2  
shows the diameters for line sets up to 100’ although vertical  
lift applications and trapping requirements need to be  
reviewed with Technical Services for line sets over 50’.  
Figure 4  
1. Install line voltage power supply to unit from a properly  
sized disconnect switch. Any excess high voltage field  
wiring should be trimmed or secured away from the low  
voltage field wiring.  
2. Ground unit at unit disconnect switch or to an earth  
ground. To facilitate conduit, a hole is in the bottom of  
the control box. Connect conduit to the control box  
using a proper conduit fitting. Units are approved for  
use only with copper conductors. 24V Class II circuit  
connections are made in the low voltage junction box.  
Refer to Figure 4 for high voltage field wiring diagram.  
A complete unit wiring diagram is located inside the unit  
control box cover.  
Installing Refrigerant Line  
During the installation of an air conditioning system, it is  
important to properly isolate the refrigerant line to prevent  
unnecessary vibration. Line set contact with the structure  
(wall, ceiling, or floor) may cause objectionable noise when  
vibration is translated into sound. As a result, more energy  
or vibration can be expected. Close attention to line set  
isolation must be observed.  
Following are some points to consider when placing and  
installing a high-efficiency outdoor unit:  
3. Install room thermostat on an inside wall that is not  
subject to drafts, direct sunshine, or other heat sources.  
4. Install low voltage wiring from outdoor to indoor unit  
and from thermostat to indoor unit. (See Wire Diagram  
on page 27.)  
5. Do not bundle any excess 24V control wire inside  
control box. Run control wire through installed wire tie  
and tighten wire tie to provide low voltage strain relief  
and to maintain seperation of field-installed low and high  
voltage circuits.  
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Placement  
Brazing Connection Procedure  
Be aware that some localities are adopting sound ordinances  
based on how noisy the unit is at the neighbor’s home, not  
at the original installation. Install the unit as far as possible  
from the property line. When possible, do not install the unit  
directly outside a bedroom window. Glass has a verry high  
level of sound transmission. Figure 5 shows how to place  
the outdoor unit and line set to reduce line set vibration.  
1. Cut ends of refrigerant lines square (free from nicks or  
dents). Debur the ends. The pipe must remain round; do  
not pinch end of line.  
2. Before making line set connections, use dry nitrogen to  
purge the refrigerant piping. This will help to prevent oxida-  
tion and the introduction of moisture into the system.  
Line Set Isolation  
3. Use silver alloy brazing rods (5% or 6% silver alloy for  
copper-to-copper brazing or 45% silver alloy for copper-to-  
brass or copper-to-steel brazing) which are rated for use  
with R410A refrigerant.  
Illustrations on pages 6 and 7 demonstrate procedures which  
ensure proper refrigerant line set isolation. Figure 6 shows  
how to install line sets on horizontal runs. Figure 7 shows  
how to make a transition from horizontal to vertical. Figure  
8 shows how to install line sets on vertical runs.  
4. Remove the Schrader core assemblies before brazing to  
protect them from damage due to extreme heat. Replace  
the cores when brazing is complete.  
Refrigerant Line Set Diameters (in.)  
5. Remove light maroon washers from service valves and  
shield light maroon stickers to protect them during brazing.  
Wrap a wet cloth around the valve body and copper tube  
stub to protect it from heat damage.  
Liquid Line  
Line S et Length and S ize  
B T UH  
12 f t. 25 ft. 50 ft. 75 ft. 100 ft.  
Outside Unit Placement & Installation  
3/8  
3/8  
3/8  
3/8  
3/8  
3/8  
3/8  
3/8  
3/8  
3/8  
3/8  
3/8  
3/8  
3/8  
1/2  
1/2  
3/8  
1/2  
1/2  
1/2  
24,000  
36,000  
48,000  
60,000  
Install unit away  
from windows  
S uction L ine  
L ine S et L ength a nd S ize  
12 f t . 25 ft. 50 ft. 75 ft. 100 ft.  
B T U H  
3/4  
3/4  
7/8  
7/8  
1/8  
3/4  
7/8  
3/4  
7/8  
24,000  
7/8  
Two 90° elbows installed in lineset  
will reduce lineset vibration  
36,000 7/8  
48,000 7/8  
60,000 1/8  
1-1/8  
1-1/8  
1-1/8  
7/8  
1-1/8 1-1/8  
Figure 5  
1-1/8  
For installations exceeding 50’, contact  
Technical Services.  
Table 2  
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6. Braze the line set to the service valve. Quench the joints  
with water or a wet cloth to prevent heat damage to the  
valve core and opening port. The tube end must stay  
bottomed in the fitting during final assembly to ensure  
proper seating, sealing, and rigidity.  
CAUTION  
When flushing existing line set and/or indoor coil, be sure to  
empty all existing traps. Residual mineral oil can act as an  
insulator, preventing proper heat transfer. It can also clog  
the thermal expansion valve, reducing system performance  
and capacity. Failure to properly flush system as explained  
in these instructions will void warranty.  
7. Install the thermal expansion valve which is sold  
separately and which is approved for use with R410A  
refrigerant in the liquid line at the indoor coil (see Refrigerant  
Metering Device on page 9).  
Refrigerant Line Sets: Installing Horizontal Runs  
To hang line set from joist or rafter,  
use either metal strapping material  
or anchored heavy nylon wire ties.  
Wire Tie  
(around vapor line only)  
8  
Strapping Material  
(around vapor line only)  
Floor Joist or  
Roof Rafter  
Tape or Wire Tie  
8’  
Strap the vapor line to the joist or rafter  
at 8intervals then strap the liquid line  
to the vapor line.  
Metal Sleeve  
Floor Joist or Roof Rafter  
Tape or Wire Tie  
Figure 6  
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Refrigerant Line Sets: Transition from Vertical to Horizontal  
Automotive  
Muffler-Type  
Hanger  
Anchored  
Heavy Nylon  
Wire Tie  
Strap Liquid  
Line to Vapor  
Line  
Strap Liquid  
Line to Vapor  
Line  
Wall  
Stud  
Wall  
Stud  
Liquid Line  
Liquid Line  
Vapor Line Wrapped  
Vapor Line Wrapped  
Metal Sleeve  
in Armaflex  
Metal Sleeve  
in Armaflex  
Figure 7  
Refrigeraant Line Sets: Installing Vertical Runs (new construction shown)  
IMPORTANT: Refrigerant  
lines must not contact wall.  
NOTE: Similar installation practices  
should be used if line set is to be  
installed on exterior of outside wall.  
Outside Wall  
Vapor Line  
Liquid Line  
Wood Block  
Between Studs  
Wire Tie  
Inside Wall  
Strap  
Sleeve  
Vapor Line Wrapped  
with Armaflex  
Wire Tie  
Liquid Line  
Outside Wall  
Wood Block  
IMPORTANT:  
Refrigerant  
lines must not  
contact structure.  
Wire Tie  
Strap  
Caulk  
Fiberglass  
PVC Pipe  
Insulation  
Sleeve  
Figure 8  
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Flushing Existing Line Set and Indoor Coil  
from the existing system. Refer to the gauges after shutdown  
to confirm that the entire system is completely void of  
refrigerant. Disconnect the liquid and suction lines from the  
existing outdoor unit.  
This procedure should not be performed on systems  
which contain contaminants, such as compressor burn  
out.  
If the existing outdoor unit is equipped with manual shutoff  
valves AND new R-22 refrigerant will be used to flush the  
system:  
Required Euipment  
The following equipment is needed to flush the existing line  
set and indoor coil (See Figure 9). Two clean R-22 recovery  
bottles, an oil-less recovery machine with a “pump down”  
feature, and two sets of gauges (one for use with R-22 and  
one for use with R410A).  
Start the existing R-22 refrigerant system in cooling mode  
and close the liquid line valve. Pump all the existing R-22  
refrigerant back into the outdoor unit.  
Flushing Procedure  
(It may be necessary to bypass the low pressure switches  
to ensure complete refrigerant evacuation.)  
IMPORTANT: The line set and/or indoor coil must be  
flushed with at least the same amount of refrigerant that  
previously charged the system. Check the charge in the  
flushing cylinder before flushing the unit.  
When the low side system pressures reach 0 psig, close  
the suction line valve. Disconnect all power to the existing  
outdoor unit. Refer to the gauges after shutdown to confirm  
that the valves are not allowing refrigerant to flow back into  
the low side of the system. Disconnect the liquid and suction  
lines from the existing outdoor unit.  
1. Remove existing R-22 refrigerant using the appropriate  
procedure.  
If the existing outdoor unit is not equipped with shutoff valves,  
or if the unit is not operational AND the existing R-22  
refrigerant will be used to flush the system:  
2. Remove the existing outdoor unit. Set the new R410A  
unit and follow the brazing connection procedure outlined  
previously on this page to make line set connections. Do  
not install the R410A thermal expansion valve at this  
time.  
Disconnect all power to the existing outdoor unit. Connect  
the existing unit, a clean recovery cylinder, and the recovery  
machine according to the instructions provided with the  
recovery machine. Remove all R-22 refrigerant  
3. Make low voltage and line voltage connections to the  
new outdoor unit. Do not turn on power to the unit or  
open the outdoor unit service valves at this time.  
Flushing Connections  
Figure 9  
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4. Remover the existing R-22 refrigerant flow control orifice  
or thermal expansion valve before continuing with flushing  
procedures. R-22 flow control devices are not approved for  
use with R410A refrigerant and may prevent proper flushing.  
Use a field-provided fitting to reconnect the lines.  
An R410A system will not operate properly with an R-22  
metering device.  
Install the refrigerant metering device as shown in Figure  
11. Do not twist cap tubes when loosening the seal nut from  
the orifice housing. Use wrench to back up the distributor.  
5. Remove the pressure tap valve cores from the 4HP18LT  
units service valves. Connect an R-22 cylinder with clean  
refrigerant to the suction service valve. Connect the R-22  
gauge set to the liquid line valve and connect a recovery  
maching with an empty recovery tank to the gauge set.  
6. Set the recovery machine for liquid recovery and start  
the recovery machine. Open the gauge set valves to allow  
the recovery machine to pull a vacuum on the existing system  
line set and indoor coil.  
7. Invert the cylinder of clean R-22 and open its valve to  
allow liquid refrigerant to flow in to the system through the  
suction line valve. Allow the refrigerant to pass from the  
cylinder and through the line set and the indoor coil before it  
enters the recovery machine.  
8. After all of the liquid refrigerant has been recovered, switch  
the recovery machine to vapor recovery so that all of the R-  
22 vapor is recovered. Allow the recovery machine to pull a  
vacuum on the sytem.  
Figure 10  
Expansion Valve Systems  
Expansion valves equipped with Chatleff-type fittings are  
available from the manufacturer. See Table 3 for proper  
TXV for each unit.  
NOTE: Asingle system flush should remove all of the mineral  
oil from the existing refrigerant lines and indoor coil. Asecond  
flushing may be done (using clean refrigerant) if insufficient  
amounts of mineral oil were removed during the first flush.  
After each system flush, allow the recovery machine to  
pull a vacuum on the system at the end of the procedure.  
TXV Data  
MODEL  
PART NUMBER  
9. Close the valve on the inverted R-22 cylinder and the  
gauge set valves. Pump the remaining refrigerant out of  
the recovery machine and turn the machine off.  
H4TXV01  
H4TXV02  
H4TXV03  
4HP18LT- 24  
4HP18LT - 36  
10. Use nitrogen to break the vacuum on the refrigerant  
lines and indoor coil before removing the recovery machine,  
gauges, and R-22 refrigerant drum. Re-install pressure tap  
valve cores into the 4SHP18LT unit’s service valves.  
4HP18LT - 48, -60  
Table 3  
To install an expansion valve (See Figure 10 above):  
11. Install the fixed orifice (or thermal expansion valve  
approved for use with R410A refrigerant) in the liquid line at  
the indoor coil.  
1. Separate the distributor assembly and remove the piston  
orifice and used teflon seal. Insert nozzle end of the  
expansion valve along with a new teflon seal into the  
distributor and tighten to 20 - 30 ft. lbs. Use backup wrench  
on all wrench flats. Overtightening will crush the teflon  
seal and may cause a leak.  
Refrigerant Metering Device  
4HP18LT units are designed for use with TXV systems.  
Refer to the appropriate following section for information on  
installing the chosen refrigerant metering device.  
2. Attach liquid line portion of distributor assembly along  
with new teflon seal to the inlet of the expansion valve.  
Tighten to 20 - 30 ft. lbs. Use backup wrench on all wrench  
flats. Overtightening will crush the teflon seal and may  
cause a leak.  
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3. Connect the external equalizer line to the equalizer port  
on the suction line and tighten to 8 ft.lbs.  
Suction Line (Ball Type) Service Valve  
Suction line (ball type) service valves function the same way  
as the other valves; the difference is in the construction (See  
Figure 12).  
4. Strap the superheat sensing bulb to the suction header.  
If installing an expansion valve on an indoor coil that  
previously used a fixed orifice, be sure to remove the existing  
fixed orifice. Failure to remove a fixed orifice when installing  
an expansion valve to the indoor coil will result in improper  
operation and damage to the system.  
The ball valve is equipped with a service port with a factory-  
installed Schrader valve. A service port cap protects the  
Schrader valve from contamination and serves as the  
primary seal.  
Leak Testing  
Manifold Gauge Set  
After the line set has been connected to the indoor and  
outdoor units, the line set connections and indoor unit must  
be checked for leaks.  
Manifold guage sets used with systems charged with R410A  
refrigerant must be capable of handling the higher system  
operating pressures. The gauges should be rated for use  
with pressures 1 - 800 on the high side and a low side of 30”  
vacuum to 250 psi with dampened speed to 500 psi. Gauge  
hoses must be rated for use at up to 800 psi of pressure  
with a 4000 psi burst rating.  
Liquid and Suction Line Service Valves  
The liquid line and suction line service valves (See Figure  
11) and service ports are used for leak teating, evacuation,  
charging, and checking charge.  
Each valve is equipped with a service port which has a  
factory-installed Schrader valve. Aservice port cap protects  
the Schrader valve from contamination and serves as the  
primary leak seal.  
To Access the Schrader Port:  
1. Remove the service port cap with an adjustable wrench.  
2. Connect gauge to the service port.  
3. When testing is completed, replace service port cap.  
Tighten finger tight, then an additional 1/6 turn.  
To Open Liquid or Suction Line Service Valve:  
Remove stem cap with an adjustable wrench.  
Use service wrench with a hex-head extension to back the  
stem out counterclockwise as far as it will go. Use a 3/16”  
hex head extension for liquid line service valves and a 5/  
16” extension for suction line service valves.  
Replace the stem cap. Tighten finger tight, then tighten an  
additional 1/6 turn.  
To Close Liquid or Suction Line Service Valve:  
1. Remove the stem cap with an adjustable wrench.  
Figure 11  
2. Use a service wrench with a hex-head extension to turn  
the stem clockwise to seat the valve. Tighten firmly.  
3. Replace the stem cap. Tighten finger tight, then tighten  
an additional 1/6 turn.  
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3. Open the high pressure side of the manifold to allow  
R410A into the line set and indoor unit. Weigh in a trace  
amount of R410A. (A trace amount is a maximum of 2 oz.  
of refrigerant or 3 lbs. pressure.) Close the valve on the  
R410A cylinder and the valve on the high pressure side of  
the manifold gauge set. Disconnect the R410A cylinder.  
4. Connect a cylinder of nitrogen with a pressure regulating  
valve to the center port of the manifold gauge set. When  
using high pressure gas such as nitrogen for this  
purpose, be sure to use a regulator that can control the  
pressure down to 1 or 2 psig.  
5. Adjust nitrogen pressure to 150 psig. Open the valve on  
the high side of the manifold gauge set to pressurize the  
line set and the indoor coil.  
6. After a short period of time, open a refrigerant port to  
make sure that an adequate amount of refrigerant has been  
added for detection (refrigerant requirements will vary with  
lenths). Check all joints for leaks. Purge nitrogen and R410A  
mixture. Correct any leaks and rechecks.  
Evacuation  
Evacuating the system of noncondensables is critical for  
proper operation of the unit. Noncondensables are defined  
as any gas that will not condense under temperatures and  
pressures present during operation of an air conditioning  
system. Noncondensables and water vapor combine with  
refrigerant to produce substances that corrode copper piping  
and compressor parts.  
Figure 12  
WARNING  
Refrigerant can be harmful if inhaled. Refrigerant must  
always be used and recovered responsibly. Incorrect  
or irresponsible use of refrigerant can result in personal  
injury or death.  
WARNING  
Do Not use a compressor to evacuate a system. Avoid  
deep vacuum operation. Extremely low vacuums can  
cause internal arcing and compressor failure. Danger  
of equipment damage. Damage caused by deep vacuum  
operation will void warranty.  
WARNING  
Never use oxygen to pressurize refrigeration or air con-  
ditioning systems. Oxygen will explode on contact with  
oil and could cause personal injury or death.  
Use a thermocouple or thermistor electronic vacuum gauge  
that is calibrated in microns. Use an instrument that reads  
down to 50 microns.  
Using an Electronic Leak Detector  
1. Connect the manifold gauge set to the service valve ports  
as follows:  
1. Connect the high pressure hose of the manifold gauge  
set to the suction valve service port. (Normally the high  
pressure hose is connected to the liquid line port; however,  
connecting it to the suction ports helps to protect the manifold  
gauge set from damage caused by high pressure.)  
Low pressure gauge to suction line service valve  
High pressure gauge to liquid line service valve.  
2. Connect micron gauge.  
2. With both manifold valves closed, connect the cylinder of  
R410A refrigerant. Open the valve on the R410A cylinder  
(vapor only).  
3. Connect the vacuum pump (with vacuum gauge) to the  
center port of the manifold gauge set.  
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4. Open both manifold valves and start vacuum pump.  
5. Evacuate the line set and indoor unit to a minimum of  
500 microns or lower. During the early stages of evacuation,  
it is desirable to close the manifold gauge valve at least once  
to determine if there is a rapid rise in pressure. A rapid rise  
in pressure indicates a relatively large leak. If this occurs,  
the leak testing procedure must be repeated.  
6. When 500 microns or lower is maintained, close the  
manifold gauge valves, turn off the vacuum pump, and  
disconnect the manifold gauge center port hose from the  
vacuum pump. Attach the manifold gauge center port hose  
to a nitrogen cylinder with pressure regulator set to 150 psig  
and purge the hose. Open the manifold gauge valves to  
break the vacuum in the line set and indoor unit. Close the  
manifold gauge valves.  
7. Shut off the nitrogen cylinder and remove the manifold  
gauge hose from the cylinder. Open the manifold gauge  
valves to release the nitrogen from the line set and indoor  
unit.  
8. Reconnect the manifold gauge to the vacuum pump,  
turn the pump on, and continue to evacuate the line set and  
indoor unit until 500 microns is maintained within a 20 minute  
period after shutting off the vacuum pump and closing the  
manifold gauge valves.  
9. When the requirements above have been met, disconnect  
the manifold hose from the vacuum pump. Open the service  
valves to break the vacuum in the line set and indoor unit.  
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Units are factory charged with the amount of R410A  
refrigerant indicated on the unit rating plate. This charge is  
based on a matching indoor coil and outdoor coil with 15’  
line set. For varying lengths of line set, refer to Table 4 for  
refrigerant charge adjustment. A blank space is provided  
on the unit rating plate to list the actual field charge.  
START-UP  
CAUTION  
If unit is equipped with a crankcase heater, it should be  
energized 24 hours before unit start-up to prevent  
compressor damage as a result of slugging.  
Refrigerant Charge Adjustment  
Liquid Line Set  
Diameter  
Oz. per 5 ft. adjust  
from 15 ft. line set*  
1. Rotate fan to check for frozen bearings or binding.  
3 oz. Per 5 ft.  
3/8 in.  
2. Inspect all factory and field-installed wiring for loose  
connections.  
* If line length is greater than 15 ft., add this amount.  
If line length is less than 15 ft., remove this amount.  
3. After evacuation is complete, open liquid line and suction  
line service valves to release refrigerant charge (contained  
in outdoor unit) into system.  
Table 4  
4. Replace the stem caps and secure finger tight, then  
tighten an additional 1/6 of a turn.  
IMPORTANT  
5. Check voltage supply at the disconnect switch. The  
voltage must be within the range listed on the unit nameplate.  
If not, do not start equipment until the power company has  
been consulted and the voltage condition corrected.  
Mineral oils are not compatible with R410A. If oil must  
be added, it must be a polyolester oil.  
If the system is void of refrigerant, clean the system using  
the procedure described below.  
6. Set thermostat for cooling demand, turn on power to  
indoor blower, and close the outdoor unit disconnect switch  
to start the unit.  
1. Use dry nitrogen to pressurized the system and check  
for leaks. Repair leaks, if possible.  
7. Recheck unit voltage with unit running. Power must be  
within range shown on unit nameplate.  
2. Evacuate the system to remove as much of the moisture  
as possible.  
Refrigerant Charging  
3. Use dry nitrogen to break the vacuum.  
4. Evacuate the system again.  
This system is charged with R410A refrigerant which  
operates at much higher pressures than R-22. The liquid  
line drier provided with the unit is approved for use with  
R410A. Do not replace it with one designed for use with R-  
22. This unit is NOT approved for use with coils which  
use capillary tubes as a refrigerant metering device.  
5. Weigh the appropriate amount of R410Arefrigerant (listed  
on unit nameplate) into the system.  
6. Monitor the system to determine the amount of moisture  
remaining in the oil. Use a test kit to verify that the moisture  
content is withing the kit’s dry color range. It may be  
necessary to replace the filter drier several times to achieve  
the required dryness level. If system dryness is not  
verified, the compressor will fail in the future.  
R410A refrigerant cylinders are rose colored.  
Refrigerant should be added through the suction valve  
in the liquid state.  
Certain R410Acylinders are identified as being equipped  
with a dip tube. These allow liquid refrigerant to be  
drawn from the bottom of the cylinder without inverting  
the cylinder. Do not turn this type of cylinder upside  
down to draw refrigerant.  
The outdoor unit should be charged during warm weather.  
However, applications arise in which charging must occur in  
the colder months. The method of charging is determined  
by the unit’s refrigerant metering device and the outdoor  
ambient temperature.  
Measure the liquid line temperature and the outdoor ambient  
temperature as outlined below:  
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Figure 13  
1. Connect the manifold gauge set to the service valve ports  
2. Conduct a leak check, then evacuate as previously  
outlined.  
as follows (See Figure 13 above):  
3. Weigh in the charge according to the total amount shown  
on the unit nameplate.  
Low pressure gauge to suction line service valve  
High pressure gauge to liquid line service valve  
If weighing facilities are not available or if unit is being  
charged during warm weather, use one of the following  
procedures.  
2. Close manifold gauge set valves. Connect the center  
manifold hose to an upright cylinder of R410A.  
3. If room temperature is below 70°F, set the room  
thermostat to call for heat. This will create the necessary  
load for properly charging the system in the cooling cycle.  
Charge Using Subcooling Method (Fixed Orifice/TXV  
Systems) - Outdoor Temperatures 65°F or Above  
If charging a fixed orifice or TXV system when the outdoor  
ambient temperature is 65°F or above, the subcooling  
method can be used to charge the unit.  
4. Use a digital thermometer to record the outdoor ambient  
temperature.  
5. When the heating demand has been satisfied, switch the  
thermostat to cooling mode with a set point of 68°F. When  
pressures have stabilized, use a digital thermometer to  
record the liquid and suction line temperatures.  
1. With the manifold gauge hose still on the liquid service  
port and the unit operating stably, use a digital thermometer  
to check the liquid line temperature. For best results, use  
the same digital thermometer to check both the outdoor  
ambient and the liquid line temperatures.  
6. The outdoor temperature will determine which charging  
method to use. Proceed with the appropriate charging  
method.  
2. At the same time, record the liquid line pressure reading.  
3. Use the temperature/pressure chart (Table 5) to determine  
the saturation temperature for the liquid line pressure  
reading.  
Charge Using Weigh-In Method (Fixed Orifice/TXV  
Systems) - Outdoor Temperatures Below 65°F  
If the system is void of refrigerant, or if the outdoor ambient  
temperature is cool, use the weigh-in method to charge the  
unit. Do this after any leaks have been repaired.  
4. Subtract the liquid line temperature from the saturation  
temperature (according to the chart) to determine subcooling.  
1. Recover the refrigerant from the unit.  
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R410A Temperature/Pressure Chart  
Temp.  
(F  
Pressure  
Psig  
Temp.  
(F  
Pressure  
Psig  
Temp.  
(F  
Pressure  
Psig  
32  
33  
100.8  
102.9  
74  
75  
214.0  
217.4  
116  
117  
396.0  
401.3  
5. Compare the subcooling value with those shown in Table  
7. If subcooling is greater than shown, recover some  
refrigerant. If subcooling is less than shown, add some  
refrigerant.  
34  
35  
36  
37  
38  
39  
40  
41  
42  
43  
44  
45  
46  
47  
48  
49  
50  
51  
52  
53  
54  
55  
56  
57  
58  
59  
60  
61  
62  
63  
64  
65  
66  
67  
68  
69  
70  
71  
72  
73  
105.0  
107.1  
109.2  
111.4  
113.6  
115.8  
118.0  
120.3  
122.6  
125.0  
127.3  
129.7  
132.2  
134.6  
137.1  
139.6  
142.2  
144.8  
147.4  
150.1  
152.8  
155.5  
158.2  
161.0  
163.9  
166.7  
169.6  
172.6  
175.5  
178.5  
181.6  
184.3  
187.7  
190.9  
194.1  
197.3  
200.6  
203.9  
207.2  
210.6  
76  
77  
220.9  
224.4  
228.0  
231.6  
235.3  
239.0  
242.7  
246.5  
250.3  
254.1  
258.0  
262.0  
266.0  
270.0  
274.1  
278.2  
282.3  
286.5  
290.3  
295.1  
299.4  
303.8  
308.2  
312.7  
317.2  
321.8  
326.4  
331.0  
335.7  
340.5  
345.3  
350.1  
355.0  
360.0  
365.0  
370.0  
375.1  
380.2  
385.4  
390.7  
118  
119  
120  
121  
122  
123  
124  
125  
126  
127  
128  
129  
130  
131  
132  
133  
134  
135  
136  
137  
138  
139  
140  
141  
142  
143  
144  
145  
146  
147  
148  
149  
150  
151  
152  
153  
154  
155  
406.7  
412.2  
417.7  
423.2  
428.8  
434.5  
440.2  
445.9  
451.8  
457.6  
463.5  
469.5  
475.6  
481.6  
487.8  
494.0  
500.2  
506.5  
512.9  
519.3  
525.8  
532.4  
539.0  
545.6  
552.3  
559.1  
565.9  
572.8  
579.8  
586.8  
593.8  
601.0  
608.1  
615.4  
622.7  
630.1  
637.5  
645.0  
78  
79  
80  
81  
Subcooling Values  
82  
83  
84  
85  
86  
87  
88  
Table 6  
89  
90  
91  
92  
93  
Charge UsingApproach Method (TXV System) - Outdoor  
Temperatures 65°F or Above  
94  
95  
96  
The following procedure is intended as a general guide and  
is for use on expansion valve systems only. For best results,  
indoor temperature should be 70°F to 80°F. Monitor system  
pressures while charging.  
97  
98  
99  
100  
101  
102  
103  
104  
105  
106  
107  
108  
109  
110  
111  
112  
113  
114  
115  
1. Record outdoor ambient temperature usig a digital  
thermometer.  
2. Attach high pressure gauge set and operate unit for  
several minutes to allow system pressures to stabilize.  
3. Compare stabilized pressures with those provided in Table  
8. 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. Pressures higher than those listed indicate that  
the system is overcharged. Pressures lower than those listed  
indicate that the system is undercharged. Verify adjusted  
charge using the approach method.  
4. Use the same digital thermometer to check liquid line  
temperature.  
72  
73  
207.2  
210.6  
114  
115  
385.4  
390.7  
5. Subtract the outdoor ambient temperature from the liquid  
line temperture to determine the approach temperature.  
Table 5  
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°
°
°
Liquid Line Temperature °F  
Outdoor Ambient Temperature °F  
Approach Temperature °F  
_
=
6. Compare the approach value with those shown in Table  
9. If the values do not agree with those provided in Table 8,  
add refrigerant to lower the approach temperature or recover  
refrigerant from the system to increase the approach  
temperature.  
Check Charge Using Normal Operating Pressures  
Use Table 7 to perform maintenance checks. Table 7 is not  
a procedure for charging the system. Minor variations in  
these pressures may be due to differences in installations.  
Significant deviations could mean that the system is not  
properly charged or that a problem exists with some  
component in the system.  
Approach Values for TXV Systems  
Table 7  
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L - Liquid  
S- Suction  
Values provided above are typical pressures. Indoor unit matchup, indoor air quality equipment, and indoor  
load will case pressures to vary.  
Table 8  
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Emergency heat is usually used during an outdoor shutdown,  
but it should also be used following a power outage if power  
has been off for over an hour and the outdoor temperature  
is below 50°F. System should be left in the emergency heat  
mode at least 6 hours to allow the crankcase heater sufficient  
time to prevent compressor slugging.  
OPERATION  
Outdoor unit and indoor blower cycle on demand from the  
room thermostat. When the thermostat blower switch is  
moved to the ON position, the indoor blower operates  
continuously.  
Defrost System  
Filter Drier  
The defrost system includes two components: the defrost  
thermostat and the defrost control.  
The unit is equipped with a large capacity bi-flow filter which  
keeps the system clean and dry. If replacement is necessary,  
replace with one of similar design and capacity. The  
replacement filter drier must be suitable for use with R410A  
refrigerant.  
Defrost Thermostat  
The defrost thermostat is located on the liquid line between  
the check/expansion valve and the distributor. When the  
defrost thermostat senses 42°F or cooler, the thermostat  
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.  
Crankcase Heater  
If unit is equipped with a crankcase heater, it should be  
energized 24 hours before unit start-up to prevent  
compressor damage as a result of slugging.  
Defrost Control  
Emergency Heat Function (Room Thermostat)  
The defrost control board includes the combined functions  
of time/temperature defrost control, defrost relay, diagnostic  
LEDS and terminal strip for field wiring connections (See  
Figure 14).  
An emergency heat function is designed into some room  
thermostats. This feature is applicable when isolation of  
outdoor unit is required or when auxiliary electric heat is  
stage by outdoor thermostats. When the room thermostat  
is placed in the emergency heat position, the outdoor unit  
control circuit is isolated from power and the field-supplied  
relays bypass the outdoor thermostats. An amber indicating  
light simultaneously comes on to remind the homeowner  
that the unit is operating in the emergency heat mode.  
The control provides automatic switching from normal  
heating operation to defrost mode and back. During the  
compressor cycle (call for defrost), the control accumulates  
compressor run time at 30, 60, 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 the defrost begins.  
Defrost Control Board  
P1  
FAN  
Defrost Interval  
30  
60  
90  
C2  
Timing Pins  
K1 Relay  
TEST  
Test Pins  
DS1  
DS2  
Diagnostic LEDs  
P5  
U2  
K2 Relay  
U1  
Compressor Delay Pins  
O-OUT  
Reversing Valve  
P2  
W1  
C
L
Low Pressure Switch  
LO-PS  
24V  
24V TerminalStrip  
Connections  
(optional)  
L
DF  
R
Defrost Thermostat  
C5  
O
Y1-OUT  
Y1  
K3 Relay  
HI-PS  
P6  
Y1  
TST PS DF  
C
R
O
High Pressure Switch  
(optional)  
Figure 14  
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Defrost Control Timing Pins  
locked out until power to the board is interrupted, then re-  
established, or until the jumper is applied to the TEST pins  
for 0.5 seconds.  
Each timing pin selection provides a different accumulated  
compressor run time period during one thermostat run 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 defrost timing jumper is factory  
installed to provide a 60 minute defrost interval. If the timing  
selector jumper is not in place, the control defaults to a 90  
minute defrost interval. The maximum defrost period is 14  
minutes and cannot be adjusted.  
NOTE: The defrost control board ignores input from the  
low pressure switch terminals as follows:  
During the TEST mode  
During the defrost cycle  
During the 90 seconds start-up period  
For the first 90 seconds each time the reversing  
Atest option is provided for troubleshooting. The test mode  
may be started any time the unit is 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 2 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 reapplied.  
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.  
Diagnostic LEDs  
The defrost board uses two LEDs for diagnostics. The LEDs  
flash a specific sequence according to the condition as  
shown in Table 9.  
Defrost Control Board  
Diagnostic LEDs  
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. The compressor will be cycled  
off for 30 seconds going in and out of the defrost mode when  
the compressor delay jumper is removed.  
NOTE: The 30-second “off” cycle is not functional when  
jumpering the TEST pins.  
Time Delay  
The timed-off delay is 5 minutes long. The delay helps to  
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.  
Pressure Switch Circuit  
The defrost control includes two pressure switch circuits. A  
high pressure switch is connected to the board’s HI-PS  
terminals(See Figure 14). The low pressure, or loss-of-  
charge pressure, switch is connected to the LPS terminals.  
Table 9  
During a single demand cycle, the defrost control will lock  
out the unit after the fifth time that the circuit is interrupted  
by an pressure switch wired to the control board. In addition,  
the diagnostic LEDs will indicate a locked-out pressure switch  
after the fifth occurrence of an open pressure switch (See  
Table 9). The unit will remain  
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System Diagnostic Module  
TRIP LED (Red) indicates there is a demand signal from  
the thermostat but no current to the compressor is detected  
by the module. The TRIP LED typically indicates the  
compressor protector is open or may indicate missing  
supply power to the compressor.  
4HP18LT units contain a diagnostic module for  
troubleshouting heat pump system failures. By monitoring  
and analyzing data from the compressor and thermostat  
demand, the module can accurately detect the cause of  
electrical and system related failure without any sensors.  
If a system problem occurs, a flashing LED indicator  
communicates the failure code.  
Interpreting the Diagnostic LEDs  
When an abnormal system condition occurs, the diagnostic  
nodule displays the appropriate ALERT and/or TRIP LED.  
The yellow ALERT LED will flash a number of times  
consecutively, pause, and then repeat the process. To  
identify a slash code number, count the number of  
consecutive flashes. Refer to Table 10 below and Table 11  
on page 20 for information on the flash codes.  
LED Description  
POWER LED (Green) indicates voltage is present at the  
power connection of the module.  
ALERT LED (Yellow) communicates an abnormal system  
condition through a unique flash code. The ALERT LED  
will flash a number of times consecutively, pause, and then  
repeat the process. The number of consecutive flashes  
correlates to a paticular abnormal condition.  
Flash Codes  
Table 10  
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Every time the module powers up, the lastALERT LED flash  
code that occurred prior to shutdown is displayed for  
60 seconds. The module will continue to display the previous  
flash code until the condition returns to normal or 21VAC is  
removed from the module. TRIP andALERT LEDs flashing  
at the same time means control circuit voltage is too low for  
operation.  
24VAC Power Wiring  
The diagnostic module requires a constant nominal 24VAC  
power supply. The wiring to the module’s R and C terminals  
must be directly from the indoor unit or thermostat. The  
module cannot be powered by R and C terminals on the  
defrost board without experiencing nuisance alerts.  
Flash Codes (cont.)  
Table 11  
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Thermostat Demand Wiring  
Miswired Module Codes  
The diagnostic module requires a thermostat demand signal  
to operate properly. The thermostat demand signal input,  
labeled Y on the module, should always be connected to  
the compressor contactor coil so that when the coil is  
energized, the demand signal input is 24VAC. When the  
coil is not energized, the demand signal input should be less  
than 0.5VAC.  
Depending on the system configuration, someALERT flash  
codes may not be active. The presence of safety switches  
affects how the system alerts are displayed by the module.  
Miswiring the diagnostic nodule will cause false LED codes.  
Table 12 Describes LED operation when the module is  
miswired and what troubleshooting action is required to  
correct the problem.  
Miswired Module Troubleshooting  
Table 12  
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MAINTENANCE  
WARNING  
Before performing maintenance operations on system,  
turn the electric power to unit OFF at disconnect  
switch(es). Unit may have multiple power supplies.  
Electrical shock could cause personal injury or death.  
Before the start of each heating and cooling season, the  
following service checks should be performed by a qualified  
service technician.  
Inspect and clean outdoor and indoor coils. The outdoor  
coil may be flushed with a water hose.  
NOTE: It may be necessary to flush the outdoor coil more  
frequently if it is exposed to substances which are corrosive  
or which block air flow across the coil (such as pet urine,  
cottonwood seeds, etc...).  
Visually inspect the refrigerant lines and coils for leakes.  
Check wiring for loose connections.  
Check voltage at the indoor and outdoor units (with units  
operating).  
Check amperage draw at the outdoor fan motor, compressor,  
and indoor blower motor. Values should be compared with  
those given on unit nameplate.  
Check, clean (or replace) indoor unit filters.  
Check the refrigerant charge and gauge the system  
pressures.  
Check the condensate drain line for free and unobstructed  
flow. Clean drain line, if necessary.  
Adjust blower speed for cooling. Measure the pressure drop  
over the coil to determine the correct blower CFM.  
Belt drive blowers: Check drive belt for wear and proper  
tensions.  
If insufficient cooling is reported, the unit should be gauged  
and refrigerant charge checked (see Refrigerant Charging  
on page 13).  
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more frequently if it is exposed to substances which are  
corrosive or which block airflow across the coil (such as pet  
urine, cottonwood seeds, etc...).  
HOMEOWNER INFORMATION  
In order to ensure peak performance, your system must be  
properly maintained. Clogged filters and blocked airflow  
prevent your unit from operating at its most efficient level.  
Heat Pump Operation  
Heat pump units have several characteristics you should be  
aware of:  
WARNING  
Heat pumps satisfy heating demand by delivering large  
amounts of warm air into the living space. This is quite  
different from gas-fired, oil-fired, or electric furnaces which  
deliver lower volumes of considerably hotter air to heat the  
space.  
Turn all electric power to unit OFF at disconnect  
switch(es) before performing any maintenance  
operations on system. Unit may have multiple power  
supplies. Electrical shock could cause personal injury  
or death.  
Do not be alarmed if you notice frost on the outdoor coil in  
the winter months. Frost develops on the outdoor coil during  
the heating cycle when temperatures are below 45°F. An  
electronic control activates a defrost cycle lasting 5 to 15  
minutes at preset intervals to clear the outdoor coil of the  
frost. A shift in sound type does occur during the defrost  
mode.  
Ask your dealer to show you where the indoor unit’s filter is  
located. It will be either at the indoor unit (installed internal  
or external to the cabinet) or behind a return air grille in the  
wall or ceiling in your home. Check the filter monthly and  
clean or replace it as needed.  
Disposable filters should be replaced with a filter of the same  
type and size. If you are unsure of the filter you need for  
your system, contact your dealer.  
During the defrost cycle, you may notice steam rising from  
the unit. This is a normal occurrence. The thermostat may  
engage auxiliary heat during the defrost cycle to satisfy a  
heating demand. The unit will return to normal operation at  
the conclusion of the defrost cycle.  
Many indoor units are equipped with reusable foam filters.  
These filters can be cleaned with a mild soap and water  
solution. Rinse the filter thoroughly and let dry completely  
before returning to unit or grille.  
In case of extended power outage....  
If the outdoor temperature is below 50°F and power to the  
outdoor unit has been interrupted for 6 hours or longer.  
observe the following when restoring power to the heat pump  
system.  
The filter and all access panels must be in place any  
time the unit is in operation.  
Some systems are equipped with an electronic air cleaner,  
designed to remove the majority of airborne particles from  
the air passing through the cleaner. If your system includes  
an electronic air cleaner, ask your dealer for maintenance  
instructions.  
Set the room thermostat selctor to the “Emergency Heat”  
setting to obtain temporary heat for a minimum of 6 hours.  
This will allow system refrigerant pressures and  
temperatures enough time to return to a stabilized condition.  
In the “Emergency Heat” mode, all heating demand is  
satisfied by auxiliary heat; heat pump operation is locked  
out. After a 6 hour “warmup” period, the thermostat can  
then be switched to the “Heat” setting and normal heat  
operation may resume.  
Inspect and clean indoor coil. The indoor evaporator coil is  
equipped with a drain pan to collect condensate formed as  
the system removes humidity from the inside air. Have your  
dealer show you the location of the drain line and how to  
check for obstructions. This also applies to an auxiliary drain,  
if one is installed.  
Thermostat Operation  
Though your thermostat may vary somewhat from the  
description below, its operation will be similar.  
Inspect and clean outdoor coil:  
Make sure no obstructions restrict airflow to the outdoor unit.  
Leaves, trash, or shrubs crowding the unit can cause it to  
work harder and use more energy. Keep shrubbery trimmed  
away from the unit and periodically check for debris which  
collects around the unit.  
Temperature Setting Levers  
Most heat pump thermostats have two temperature selector  
levers: one for heating and one for cooling. Set the levers  
or dials to the desired temperature setpoints for both heating  
and cooling. Avoid frequent temperature adjustment; turning  
the unit off and back on before presssures equalize puts  
stress on unit compressor.  
The outdoor coil may require frequent cleaning, depending  
on environmental conditions. Clean the outdoor coil with an  
unpressurized water hose to remove surface contaminants  
and debris. It may be necessary to flush the outdoor coil  
506470-01  
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Fan Switch  
Preservice Check  
In AUTO or INT (intermittent) mode, the blower operates  
only when the thermostat calls for heating or cooling. This  
mode is generally preferred when humidity control is a priority.  
The ON or CONT mode provides continuous indoor blower  
operation, regardless of whether the compressor or auxiliary  
heat are operating. This mode is required when constant  
air circulation or filtering is desired.  
If your system fails to operate, check the following before  
calling for service:  
Check to see that all electrical disconnect switches ar ON.  
Make sure the thermostat temperature selector is properly  
set.  
System Switch  
Make sure the thermostat system switch is properly set.  
Replace any blown fuses, or reset circuit breakers.  
Make sure unit access panels are in place.  
Make sure air filter is clean.  
Set the system switch for heating, cooling, or auto operation.  
The auto mode allows the heat pump to automatically switch  
from heating mode to cooling mode to maintain  
predetermined comfort settings. Many heat pump  
thermostats are also equipped with an emergency heat mode  
which locks out heat pump operation and provides temporary  
heat supplied by the auxiliary heat.  
Locate unit model number and have it handy before calling.  
Indicating Light  
Most heat pump thermostats have an amber light which  
indicates when the heat pump is operating in the emergency  
heat mode.  
Temperature Indicator  
The temperture indicator displays the actual room  
temperature.  
Programmable Thermostats  
Your system may be controlled by a programmable  
thermostat. These thermostats provide the added feature  
of programmable time-of-day set points for both heating and  
cooling. Refer to the user’s information manual provided  
with your particular thermostat for operation details.  
506470-01  
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Page 25  
Start-Up and Performance Checklist  
Job Name _____________________________  
Job No. ____________  
City _______________  
City _______________  
Date ___________  
State ___________  
State ___________  
Job Location ___________________________  
Installer _______________________________  
Unit Model No. _________________________  
Service Technician _______________________  
Serial No._____________________________  
Nameplate Voltage _____________________  
Rated Load Ampacity _________  
Maximum Fuse or Circuit Breaker ________________________  
Electical Connections Tight? Indoor Filter Clean? Supply Voltage (Unit Off) __________  
Compressor Amperage ________ Outdoor Fan __________  
Indoor Blower RPM ___________________ S.P. Drop Over Indoor (Dry) ____________________  
Outdoor Coil Entering Air Temperature ________ Voltage with Compressor Operating __________  
Outdoor Fan Checked?  
Cooling  
Liquid Line Pressure _______ Suction Line Pressure _______ Refrigerant Charge Checked?  
Heating  
Liquid Line Pressure _______ Suction Line Pressure _______ Refrigerant Charge Checked?  
Refrigerant Lines: Leak Checked?  
Properly Insulated?  
Caps Tight?  
Properly Set?  
Service Valves: Fully Opened?  
Thermostat: Calibrated?  
Sequence of Operation  
Heating Correct?  
Level?  
Cooling Correct?  
506470-01  
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Page 26  
Wire Diagram  
LT BLUE  
RED  
OUTDOOR  
FAN  
BLUE  
YELLOW  
BLACK  
GREEN  
DUAL CAPACITOR  
RED  
FAN  
THERMOSTAT  
W1  
Y1 Y2  
C
R
O
F
C
H
BLACK  
RED  
O-OUT  
LO-PS  
W1  
W1  
L
C
L
C
L
24V  
R
R
YELLOW  
C
DF  
COMMON  
O
Y1  
O
Y1  
BLUE  
Y1 OUT  
HI-PS  
BLACK  
R
S
DEFROST CONTROL  
COMPRESSOR  
A132  
YELLOW  
CRANKCASE HEATER  
L2  
208-230/60/1  
1
L1  
GROUND  
LUG  
GROUND  
THERMOSTAT  
CMC1  
S40  
Y2  
W1  
Y1  
C
R
O
FAN  
REVERSING  
VALVE  
O-OUT  
LO-PS  
L1  
W1  
DEFROST  
THERMOSTAT  
L
C
L
B1  
S87  
24V  
S6  
K1  
R
DF  
COMMON  
BLACK  
L1  
C
S
R
BLUE  
O
1
K1-1  
Y1  
Y1 OUT  
HI-PS  
A132  
Y2 Y1  
L
R
C
208-230/60/1  
L2  
S4  
YELLOW  
RED  
RED  
ORANGE  
YELLOW  
LT BLUE  
FAN  
HR1  
BLACK  
CMC1  
F
S40  
H
C
EQUIPMENT  
GROUND  
B4  
C12  
PURPLE  
DESCRIPTION  
COMPONENT  
KEY  
A132  
B1  
DIAGNOSTIC MODULE  
COMPRESSOR  
FOR USE WITH COPPER  
1
LO-PS  
CONDUCTORS ONLY. REFER  
TO UNIT RATING PLATE  
FOR MINIMUM CIRCUIT  
AMPACITY AND MAXIMUM  
OVERCURRENT PROTECTION  
SIZE.  
WARNING--  
ELECTRIC SHOCK HAZARD, CAN  
CAUSE INJURY OR DEATH. UNIT  
B4  
MOTOR - OUTDOOR FAN  
CAPACITOR - DUAL  
S87  
C12  
CMC1  
HR1  
K1-1  
L1  
LOW PRESSURE  
SWITCH  
CONTROL-DEFROST  
HEATER - COMPRESSOR  
CONTACTOR - COMPRESSOR  
VALVE - REVERSING  
MUST BE GROUNDED IN ACCORDANCE  
WITH NATIONAL AND LOCAL CODES.  
HI-PS  
S4  
SWITCH - HIGH PRESSURE  
SWITCH - DEFROST  
S6  
DENOTES OPTIONAL COMPONENTS  
LINE VOLTAGE FIELD INSTALLED  
S4  
S40  
S87  
THERMOSTAT - CRANKCASE  
SWITCH - LOW PRESSURE  
HIGH PRESSURE  
SWITCH  
CLASS II  
VOLTAGE FIELD INSTALLED  
24 VOLT FACTORY INSTALLED  
48630-001  
506470-01  
Issue 1007  
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Page 27  
NOTES  
506470-01  
Issue 1007  
Page 28  
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