Carrier 38QUA009DS, Service Manual, Page: 73 / 116

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5). Turn on the air conditioner in cooling mode.
Turn it off when the gauge indicates
-0.1MPa(14.5Psi).
6).Immediately close the 3-way valve
Do this quickly so that the gauge displays a
value between 0.3 to 0.5 Mpa(43.5 to 72.5Psi).
Disconnect the charge set, and tighten the
2-way and 3-
way valves’ stem nuts.
Use a torque wrench to tighten the 3-way valves
service port cap to a torque of 18N.m.
Be sure to check for gas leaks.
2. Air Purging by the Refrigerant
Procedure:
1). Confirm that both the 2-way and 3-way
valves are closed.
2). Connect the charge set and a charging
cylinder to the service port of the 3-way valve
Leave the valve on the charging cylinder closed.
3). Purge the air from the charge hose.
Open the valves on the charging cylinder and
the charge set. Purge the air by loosening the
flare nut on the 2-
way valve approximately 45’
for 3 seconds and then closing it for 1 minute.
Repeat 3 times.
After purging the air, use a torque wrench to
tighten the flare nut on the 2-way valve.
4). Check for gas leaks
Check the flare connections for gas leakage.
5). Discharge the refrigerant.
Close the valve on the charging cylinder and
discharge the refrigerant by loosening the flare
nut on the 2-
way valve approximately 45’ until
the gauge indicates 0.3 to 0.5 Mpa(43.5 to
72.5Psi)
6). Disconnect the charge set and the charging
cylinder, and open the 2-way and 3-way valves
Be sure to use a hexagonal wrench to operate
the valve stems.
7). Mount the valve stems nuts and the service
port cap.
Be sure to use a torque wrench to tighten the
service port cap to a torque 18N.m.
Be sure to check for gas leakage.
13.4.6 Re-Installation When the Outdoor
Unit Requires Repairs
1. Evacuation for the whole system
Procedure:
1).Confirm that both the 2-way and 3-way
valves are open.
2). Connect the vacuum pump to 3-
way valve’s
service port.
3). Conduct an evacuation for approximately
one hour. Confirm that the compound meter
displays a value of -0.1Mpa(14.5Psi).
4). Close the valve (Low side) on the charge set,
turn off the vacuum pump. After 5 minutes,
confirm that the gauge needle is not moving.
5). Disconnect the charge hose from the
vacuum pump.
2. Refrigerant charging