Condensing Unit & Heat Pump R410A Service Manual
117
SERVICING
LOW SIDE
GAUGE
AND VALVE
HIGH SIDE
GAUGE
AND VALVE
TO
UNIT SERVICE
VALVE PORTS
VACUUM PUMP
VACUUM PUMP
ADAPTER
800 PSI
RATED
HOSES
CHARGING
CYLINDER
AND SCALE
S-103 CHARGING
* Do not overcharge system with refrigerant.
* Do not operate unit in a vacuum or at negative
pressure.
Failure to follow proper procedures may cause
property damage, personal injury or death.
WARNING
REFRIGERANT UNDER PRESSURE!
CAUTION
Use refrigerant certified to AHRI standards. Used
refrigerant may cause compressor damage and is
not covered under the warranty. Most portable
machines cannot clean used refrigerant to meet
AHRI standards.
CAUTION
with the suction valve closed is not covered under the
Damage to the unit caused by operating the compressor
warranty and may cause serious compressor damage.
Charge the system with the exact amount of refrigerant. Refer
to the specicaon secon or check the unit nameplates for the
correct refrigerant charge. An inaccurately charged system will
cause future problems.
NOTE: R410A should be drawn out of the storage container
or drum in liquid form due to its fraconaon properes, but
should be “Flashed” to its gas state before entering the system.
There is commercially available restricon devices that t into
the system charging hose set to accomplish this. DO NOT charge
liquid R410A into the compressor.
NOTE: Power must be supplied to the 18 SEER outdoor units
containing ECM motors before the power is applied to the
indoor unit. Sending a low voltage signal without high voltage
power present at the outdoor unit can cause malfuncon of the
control module on the ECM motor.
Adequate refrigerant charge for the matching evaporator
coil or air handler and 15 feet of line set is supplied with
the condensing unit. If using evaporator coils or air handlers
other than HSVTC coil it may be necessary to add or remove
refrigerant to aain proper charge. If line set exceeds 15 feet
in length, refrigerant should be added at .6 ounces per foot of
liquid line.
NOTE: The outdoor temperature should be 60°F or higher
when charging the unit.Charge should always be checked using
subcooling when using TXV equipped indoor coil to verify proper
charge. Open the sucon service valve rst! If the liquid service
valve is opened rst, oil from the compressor may be drawn
into the indoor coil TXV, restricng refrigerant ow and aecng
operaon of the system.
When opening valves with retainers, open each valve only unl
the top of the stem is 1/8” from the retainer. To avoid loss
of refrigerant, DO NOT apply pressure to the retainer. When
opening valves without a retainer remove service valve cap and
insert a hex wrench into the valve stem and back out the stem
by turning the hex wrench counterclockwise. Open the valve
unl it contacts the rolled lip of the valve body.
NOTE: These are not back-seang valves. It is not necessary to
force the stem ghtly against the rolled lip.
Aer the refrigerant charge has bled into the system, open the
liquid service valve. The service valve cap is the secondary seal
for the valve and must be properly ghtened to prevent leaks.
Make sure cap is clean and apply refrigerant oil to threads and
sealing surface on inside of cap. Tighten cap nger-ght and
then ghten addional 1/6 of a turn (1 wrench at) to properly
seat the sealing surfaces.
EXPANSION VALVE SYSTEM
NOTE: Units matched with indoor coils equipped with non-
adjustable TXV should be charged by subcooling only.
NOTE: The TXV should NOT be adjusted at light load condions
55º to 60ºF. Use the following guidelines and methods to check
unit operaon and ensure that the refrigerant charge is within
limits. Charge the unit on low stage.
Units Equipped with Adjustable Expansion Valves should be
charged by Subcooling and Superheat adjusted only if