TM 9-4120-403-14
Inspection
(1) Check wire leads for tightness. Tighten if loose.
(2) Check switch for evidence of damage. Replace if damaged.
Removal
(1) Tag and unsolder wire leads.
(2) Remove two screws, washers, locknuts, and heater cutout (thermostat) switch.
Test
With thermostat at room temperature, use a multimeter set on the lowest OHMS scale to check for continuity
between each pair of contacts (4 and 6, 4 and 5, and 5 and 6). If continuity is not indicated between all contacts, replace
the thermostat.
NOTE
For full operational test of thermostat use an external heat source. Thermostat should open (no continuity
across contacts) when temperature reaches 194F f160 (610 C 9-o).
Installation
(1) Secure thermostat to heater support with two screws, washers, and locknuts.
(2) See tags and wiring diagram (fig. 4-43) solder wire leads, and remove tags.
Follow-on procedure:
(1) Install heater elements HR4, HR5, HR6. (See para 4-58.)
(2) Install top panel. (See para 4-16.)
4-135
