TM 9-4120-407-14
4-18. CHARGING THE REFRIGERANT SYSTEM. (Cont)
(12) Close charge and pressure gauge valves.
NOTE
If 6.2 pounds (2.8 kg) full charge was obtained, skip steps (13)
through (23).
(13) Connect power at power source.
(14) Turn air conditioner on and operate in COOL mode with potentiometer TEMPERATURE control set
at maximum COOL position.
Never introduce liquid refrigerant into the low pressure (suction)
charging valve. This can cause damage to the compressor.
(15) Set refrigerant cylinder to deliver gas only.
Never introduce high discharge pressure into a refrigerant cylinder.
This can cause the cylinder to rupture and injure personnel.
(16) Check that pressure gauge valve is closed.
(17) Open compound gauge valve.
(18) Open charge valve.
(19) Monitor weight of the refrigerant drum as air conditioner compressor pulls additional refrigerant
gas into system until fully 6.2 pounds (2.8 kg) charge is obtained. When system is fully charged,
immediately close refrigerant drum valve and air conditioner suction service valve.
(20) Run air conditioner in COOL mode
(with potentiometer TEMPERATURE control in full COOL position) for 15 minutes.
(21) With the Air Conditioner running, observe sight glass on back of condenser section. Be sure that
the compressor is running.
(a) Green center means refrigerant moisture content is acceptable.
(b) Yellow center means there is too much moisture in system. It must be discharged, evacuated
and charged again.
(22) Close compound gauge, charge, and refrigerant cylinder valves.
(23) Turn rotary MODE selector switch to OFF RESET.
4-44
