Figure 4-26.1. Thermostatic Switches (S2 and S3)

TM 5-4120-359-14

Removal - Model EKP

Figure 4-26.1. Thermostatic Switches (S2 and S3) - Models EKP and FGG.

(1) Using screwdriver and wrench, remove the four screws and flat washers, four lockwashers, eight spacers and

nuts, that hold the thermostatic switches to the bracket and to the frame.

(2) Remove the switches and bracket from the unit.

(3) Using screwdriver, tag and remove leads from thermostatic switch.

d. Inspect/Bench test

(1) Inspect for cracks, loose connections, and obvious damage. Replace, if defective.

(2) Tape the bulb of a thermometer or junction of a thermocouple to the body of a thermostatic switch, and

connect the multimeter to terminals one and two. Use a 50 watt bulb or a heat source. Gradually apply heat while

observing both the thermometer and the multimeter. Continuity should drop out at 145 to 155F (63 to 68C). Remove

heat source and let the thermostat cool while observing the thermostat and multimeter. Continuity should be re-

established at 100 to 120F (38 to 49C).

(3) Repeat step (2) with meter connected to terminals 3 and 4.

Change 5 4-69