ARMY TM 9-4120-380-14
AIR FORCE TO 35E9-136-21
5.16. REFRIGERANT PRESSURE CHECK. Continued
SERVICE - Continued
(a) If discharge and suction pressures are at, or near, same value, a pressure equalizer solenoid valve
malfunction or an internal compressor failure is indicated
It discharge pressure is low and suction pressure is normal (see table 5-2), a low refrigerant charge is
(c) If discharge pressure is normal and suction pressure is either high or low, failure or maladjustment of the
pressure regulator valve or expansion valve is indicated.
(d) If discharge pressure is high and suction pressure is normal,
refrigerant overcharge, or clogged filter drier is indicated.
When pressure tests are completed, proceed with maintenance action indicated.
Turn MODE SELECT switch to OFF
(10) Disconnect air conditioner input power at source.
(11) Remove service manifold hoses from service valves.
(12) Install protective caps (paragraph 5.9) to high (discharge) and low pressure (suction) service valve stems