56 Room Air Conditioner
Troubleshooting Guide
Pumping Down
3-way Valve• Procedure
(1) Confirm that both liquid side and gas side
valves are set to the open position.
– Remove the valve stem caps and confirm that
the valve stems are in the raised position.
–Be sure to use a hexagonal wrench to operate
the valve stems.
(2) Operate the unit for 10 to 15 minutes.
(3) Stop operation and wait for 3 minutes, then
connect the charge set to the service port of
the Gas side valve.
– Connect the charge hose to the service port.
(4) Air purging of the charge hose.
– Open the low-pressure valve on the charge set
slightly to air purge from the charge hose.
(5) Set the liquid side valve to the closed position.
(6) Operate the air conditioner in cooling mode
and stop it when the gauge indicates
1kg/cm2g.
(7) Immediately set the Gas side valve to the
closed position.
– Do this quickly so that the gauge ends up indi-
cating 3 to 5kg/cm2g.
(8) Disconnect the charge set, and mount the
Liquid side and Gas side valve’s stem nuts
and the service port nut.
– Use torque wrench to tighten the service port
nut to a torque of 1.8 kg.m.
– Be sure to check for gas leakage.
Lo
Closed
Purge the air
Outdoor unit
Indoor unit Liquid side
Gas side
CLOSE
Open
3-Way
valve
3-Way
valve
CLOSE