4-29. THERMOSTATIC SWITCHES (S2 and S3)
Preliminary Procedure: 1. Disconnect power.
2. Remove top evaporator cover. (See paragraph 3-21.)
Disconnect input power from the air conditioner before performing maintenance
on any part of the electrical system. The voltages used can be lethal.
Test switch when the temperature is below 100°F (38°C).
(1) Tag leads, using screwdriver, remove four screws that hold leads to switch. (There are two switches.)
Figure 4-25. Thermostatic Switch Test (Model DHF)
(2) Test for continuity between switch terminals 1 and 2 and between 3 and 4.
If none, switch should be
Switch contacts should open at 145-155°F (63-68° C) and close when temperature
drops to 100-120°F (38-49°C).
4-68 Change 2
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