Figure 4-84. High Pressure Switch (S4)

TM 5-4120-359-14

a. Inspect

(1) Check that mounting screws and terminal attachment screws are in place and secure. Tighten if loose.

Replace if missing.

(2) Check that capillary line is not kinked, mashed, or broken. Replace switch if capillary line is damaged.

Figure 4-84. High Pressure Switch (S4)

b. Test. Press and release reset button on switch. Use a continuity tester or multimeter to check for continuity

between terminals 1 and 2 on switch. If there is continuity, the switch is properly closed. If no continuity is found, press

and release reset button again. If there is still no continuity, switch must be replaced.

Removal

(1) Discharge the refrigerant system per paragraph 4-5.

(2) While purging the system with nitrogen, debraze the capillary end from the tube tee. (See paragraphs 4-6

(3) Using a screwdriver, remove the screw and clamp from the coil of capillary tubing.

(4) Tag and disconnect the two leads.

(5) Using an offset screwdriver or wrench, remove two screws holding the pressure switch.

(6) Remove the pressure switch.

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