3. Gas Charging
(After Evacuation)
• Procedure
(1) Connect the charge hose to the charging
cylinder.
– Connect the charge hose which you dis-
connected from the vacuum pump to the valve
at the bottom of the cylinder.
– If you are using a gas cylinder, also use a scale
and reverse the cylinder so that the system can
be charged with liquid.
(2) Purge the air from the charge hose.
– Open the valve at the bottom of the cylinder
and press the check valve on the charge set to
purge the air. (Be careful of the liquid
refrigerant). The procedure is the same if
using a gas cylinder.
(3) Open the valve (Lo side on the charge set and
charge the system with liquid refrigerant.
– If the system can not be charged with the
specified amount of refrigerant, it can be
charged with a little at a time (approximately
150g each time) while operating the air
conditioner in the cooling cycle; however, one
time is not sufficient, wait approximately 1
minute and then repeat the procedure
(pumping down-pin).
(4) Immediately disconnect the charge hose from
the 3-way valve’s service port.
– Stopping par tway will allow the gas to be
discharged.
– If the system has been charged with liquid
refrigerant while operating the air conditioner
turn off the air conditioner before disconnecting
the hose.
(5) Mount the valve 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.
\
This is different from previous procedures.
Because you are charging with liquid refrigerant
from the gas side, absolutely do not attempt to
charge with larger amounts of liquid refrigerant
while operating the air conditioner.
Lo
Charging
cylinder
Outdoor unit
Indoor unit
Liquid side
Gas side
CLOSE
Open
2(3)-Way
valve
3-Way
valve
OPEN
Open
Check valve
(1)
–32–
