INSPECTION - TM-5-4120-393-140140

TM 5-4120-393-14

4-37.

TEMPerature Control Thermostat (S1) (cont)

INSPECTION

Check that leads are properly connected. See wiring diagram, para 4-13.

Check that capillary line and sensing bulb are not damaged.

Check TEMPerature control thermostat for signs of overheating or other obvious damage. Replace if damaged.

TESTING

Using multimeter, place probes on the red and blue terminals.

Turn TEMPerature control thermostat shaft fully clockwise.

Check continuity. If temperature at sensing bulb is above 40F (5 C), there should be no continuity.

Slowly turn shaft counterclockwise until continuity is indicated. Turn shaft back and forth slightly to check that switch

contacts open and close on a very narrow band.

Using multimeter, place probes on the red and yellow terminals.

Turn TEMPerat ure control thermostat shaft fully counterclockwise.

Check continuity. If temperature at sensing bulb is below 90F (32 C), there should be no continuity.

Slowly turn shaft clockwise until continuity is indicated. Turn shaft back and forth slight ly to check that switch contacts

open and close on a very narrow band.

Replace TEMPerature control thermostat if it fails any of the above tests.

INSTALLATION

CAUTION

Take care that sensing bulb capillary line is not kinked or mashed.

Using scre wdriver and wrench, secure TEMPerature control thermostat (9) to rear panel (5) with four screws (7) and

nuts (8).

See tags and wiring diagram, para 4-13, and connect leads.

Place capillary line through notch and split grommet (10) in rear panel.

Insert rear panel (5) into box (6) and align holes.

Using screwdriver and wrench, secure rear panel (5) with four screws (3) and nuts (4).

Place TEMPerature control thermostat knob (1) on shaft and align setscrew (2) with flat on shaft.

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