Defrost Thermostat (Emergency Heat Switch) - Whirlpool ATE0743SPP Technical Manual

Disconnect power before servicing.
Replace all parts and panels before operating.
Failure to do so can result in death or electrical shock.
DEFROST THERMOSTAT
(EMERGENCY HEAT SWITCH)
Refer to page 4-5 for the procedure for servic-
ing the defrost thermostat.
NOTE: Continuity will be read between termi-
nals 2 and 3, providing the temperature of the
capillary tube is above 25°F (–4°C). If the
temperature at the capillary tube is above 52°F
(11°C), it may be necessary to place the end of
the capillary tube in ice water to determine if the
control is sensing temperature changes.
Electrical Shock Hazard
1. Unplug air conditioner or disconnect power.
2. Disconnect the wires from the thermostat
terminals.
3. Turn the screwdriver control to the fully
counterclockwise (emergency heat) posi-
tion.
4. Set the ohmmeter to the R x 1 scale.
5. Clip the black (–) ohmmeter test lead to
terminal 2 (C2) and leave it there.
6. Touch the positive (+) ohmmeter test lead
to terminal 1 (H1). The meter should indi-
cate a closed (0 Ω) circuit.
7. Touch the positive (+) ohmmeter test lead
to terminal 3 (L3). The meter should indi-
cate an open (infinite) circuit.
8. Rotate the screwdriver control clockwise.
When the control reaches its setpoint, the
meter should indicate a closed (0 Ω) cir-
cuit.
5-3