Installation Guide
9
REFRIGERANT CHARGING
 WARNING:
This split system heat pump is shipped charged 
with R410A refrigerant and ready for installation. 
If repairs make it necessary for evacuation and 
charging, it should only be attempted by qualified 
trained personnel thoroughly familiar with this 
equipment. Under no circumstances should 
the owner attempt to install and/or service this 
equipment. Failure to comply with this warning 
could result in property damage, personal injury, 
or death.
After refrigerant line connections are completed, it is 
required that you leak check and evacuate the indoor 
section and all line connections (using proper methods) 
before finalizing the full system refrigerant charge.
• Toachieveratedcapacityandefciency,thecompressor
must be exposed to refrigerant for at least 24 hours 
prior to running and then the compressor must be run 
for a minimum of 12 hours.
• Coolingmodechargingchartsandtablesareapplicable
only to matched assemblies of this equipment and listed 
airflows for the indoor coil. Refer to the Quick Reference 
Data sheet for additional charging information. 
Outdoor units with non-AHRI listed indoor coils are not 
recommended and deviations from rated airflows or 
non-listed combinations may require modification to the 
expansion device and refrigerant charging procedures 
for proper and efficient system operation. For correct 
system charging, refer to Figure 6 (page 10), Figure 
7 (page 11), Figure 8 (page 11), Figure 9 (page 
12),  Figure 10 (page 12),  Figure 11 (page 13), & 
Figure 12 (page 13) and Table 5 (page 14),  Table 
6 (page 14), Table 7 (page 15),  Table 8 (page 
15), Table 9 (page 16),  Table 10 (page 16), & 
Table 11 (page 17).
• Therefrigerantchargecanbecheckedandadjusted
through the service ports provided external to the 
outdoor unit. Use only gage line sets which have a 
“Schrader” depression device present to actuate the 
valve. A common suction port for heating mode charging 
is included and located on the compressor access 
panel above the outdoor unit service valves.
• HeatModeVericationTablesareprovidedforquick
reference when the unit is in heating mode and for the 
inspection of the liquid line pressures and temperatures. 
See Table 12 (page 19), Table 13 (page 19), Table 
14 (page 19), Table 15 (page 19),  Table 16 (page 
20), Table 17 (page 20), & Table 18 (page 20).
• Ahigh-pressureswitchisfactory-installedandlocated
in the compressor discharge line internal to the 
outdoor unit. The switch is designed to de-energize 
the system when very high pressures occur during 
abnormal conditions. Under normal conditions, the 
switch is closed. If the discharge pressure rises above 
575 psig, then the switch will open and de-energize 
the outdoor unit. The switch will close again once the 
liquid pressure decreases to 460 psig. Please note that 
the switch interrupts the thermostat inputs to the unit. 
When the switch opens and then closes, there will be 
a 5 minute short cycling delay before the outdoor unit 
will energize.
Charging the Unit in AC Mode
(With Outdoor Temperatures Above 55° F for Optimized 
Sub-Cooling of 10° F to 12° F)
1. With the system operating at steady-state, measure the 
liquid refrigerant pressure (in psig) at the outdoor unit 
service valve.
2. Measure the liquid refrigerant temperature (in 
Fahrenheit) at the service valve.
3. Determine the required liquid refrigerant pressure from 
Figure 6, Figure 7, Figure 8, Figure 9, Figure 10, Figure 
11, & Figure 12.
• IfthepressuremeasuredinStep1isgreaterthan
the required liquid refrigerant pressure determined in 
Step 3, then there is too much charge in the system. 
Remove refrigerant and repeat Steps 1 through 3 
until the system is correctly charged.
• IfthepressuremeasuredinStep1islessthanthe
required liquid refrigerant pressure determined in 
Step 3, there is too little charge in the system. Add 
refrigerant and repeat Steps 1 through 3 until the 
system is correctly charged.










