8
REFRIGERANT CHARGING
WARNING:
SH1QE4M1SP split system heat pumps are
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.
• To achieve rated capacity and efficiency, the compressor
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.
• Refrigerant charging charts are applicable only to matched
assemblies of this equipment and listed airflows for the
indoor coil. For correct system charging, refer to
,
,
, and
.
• Refer to the unit's Quick Reference Data sheet to
determine if additional refrigerant will need to be
weighed-in to attain the base refrigerant amount for
the system match that is being installed. Please note
that the charge additons provided in the QRD are
estimates based on test data and should only be used
as a starting point. Complete the steps in the charging
procdure to obtain the final system charge.
• Use of SH1QE4M1SP 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.
• The refrigerant charge can be checked and adjusted
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.
• A high-pressure switch is factory-installed and located 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 65° 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 appropriate liquid refrigerant pressure from
.
• If the pressure measured in Step 1 is greater than
the 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.
• If the pressure measured in Step 1 is less than the
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.
Charging Charts & Application Notes
(Cooling Mode Only)
• This unit’s cooling system contains refrigerant under
high pressure. Always use safe and environmentally
sound methods when handling refrigerant handling
or servicing the unit. Review the factory literature and
safety warnings prior to servicing.
• When repairing system leaks, always use a nitrogen (inert)
gas to protect the refrigerant system and pressure check the
repair before re-charging. Always replace the filter-dryers
when performing any repair to the refrigeration system with
one capable of acid removal. After completing the repairs,
evacuate the system to 350 - 500 microns and weigh in
the refrigerant to the amount specified on the unit rating
label.
• The charging charts are valid for a variety of indoor, return
air conditions and are most influenced by the outdoor
ambient temperature, outdoor fan operation and the unit
operating voltage.
• Before using these charts, make sure the unit is in a
stable operating mode. As shown in the charts the ideal
system sub-cooling can vary over the range of operation.
Reference
,
,
to determine the ideal amount of sub-cooling
for a given liquid pressure. Units charged to other values
will not perform at the rated unit efficiency (EER) or rated
Coefficient of Performance (COP) in heating mode.
• To inspect a systems operation using quality instruments,
match the measured liquid temperature to the units chart.
The measured liquid pressure reading should be within
3% of the charts value for most installations.
• For systems that are operating with more than a 5%
deviation, inspect the unit for the proper voltage and phase
balance and the refrigeration system for leaks.
• Units that are operating at less then 95% of the nominal
voltage or with a 2% phase imbalance may see a more
significant deviation than the amount stated above.
•
DO NOT use the charts in systems that have a fan cycling
under low-ambient control. Refer to the low-ambient kit
instructions for more information. (If applicable)
