Section III. CRANKCASE PRESSURE REGULATING VALVE

TM 5-4110-217-14

Section III. CRANKCASE PRESSURE REGULATING VALVE

clockwise to raise pressure and counterclockwise to

6-14.

General.

lower pressure as observed on suction pressure gauge.

The crankcase pressure regulating valve is

b. Removal.

designed to limit the maximum pressure at the

(1) Refer to paragraph 6-1 and pump down

compressor inlet to prevent overloading the engine. At

refrigeration system.

high load conditions, the valve imposes a partial

(2) Unsweat the two copper tubes (12 and

restriction in the suction line. When the condition has

14) joining the valve (13) to the refrigeration system and

passed, and suction pressures drop below the valve

remove valve.

setting, the valve assumes an open position. The correct

c. Cleaning and Inspection.

pressure of the valve is between 8 and 10 pounds.

(1) Clean valve with an approved cleaning

solvent and dry thoroughly.

6-15.

Crankcase Pressure Regulating Valve.

(2) Inspect valve for dents, cracks, or other

damage. Valve must be replaced if defective.

(1) Operate unit with 70F air passing through

d. Installation.

evaporator coil for five minutes and read suction

(1) Place valve (13) in position and resweat

pressure gauge.

copper tubes (12 and 14).

(2) If pressure needs adjustment, remove

(2) Refer to paragraph 6-6 and purge the

protector cap from valve adjustment and then using a

refrigeration system.

screwdriver, adjust the valve. Turn adjustment

(3) Refer to paragraph 6-9 and test for leaks.

6-7