TM 10-4520-259-13&P
c.
Disconnect red and orange wires.
d.
Perform continuity check on red wire from operating control thermostat. Perform continuity
check on orange wire from high limit switch.
e.
If correct readings do not register, leave one lead on red, place other lead on common terminal
of high limit switch.
f.
Rotate shaft on operating control clockwise until click is heard. Reading should be zero ohms.
Counterclockwise should read infinity. If these readings do not register, replace the operating control. If
readings do register, replace the high limit control.
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