Section V. PRESSURE RELlEF VALVE

TM 5-4120-273-15

Figure 6-1. Solenoid valve, disassembly and assembly.

Section V. PRESSURE RELlEF VALVE

system (para 5-21b). Refer to figure 3-6 and re-

6-11. Pressure Relief Valve

move pressure relief valve.

a. General. The pressure relief valve protects

c. Installation. Refer to figure 3-6, and install

the refrigerant system from excessive pressure.

pressure relief valve. Evacuate (para 5-21c), and

recharge (para 5-21d and refrigerant system.

b. Removal. Slowly discharge refrigerant from

Section VI. EXPANSION VALVES

(3) Refer to figures 3-11 and 3-12 and re-

6-12. Expansion Valves

move expansion valves.

a. General. The main expansion valve controls

c. Adjustment.

the flow of refrigerant to the evaporator coil dur-

(1) Remove side cap from expansion valve

ing the cooling cycle of operation. The bypass ex-

base.

pansion valve functions when the unit is in the by-

Note. Make sure thermal bulb is securely fastened

pass cycle of operation.

to suction line and the bulb is covered with rubber insula-

tion.

b. Removal.

(1) Remove cover panel, reference para-

(2) Turn stem clockwise for higher super-

graph 3-18.

heat and counterclockwise for lower superheat.

One full turn is equivalent to approximately 2F

(2) Discharge refrigerant from system, ref-

superheat. A suction gas superheat of 5F to 10F

6-3