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Evaporator Fan Does Not Operate
Check for the following problems:
1.
Evaporator fan faulty.
2.
115 VAC not present at evaporator fan.
The
compressor, condenser fan, and evaporator
fan should always operate at the same time. If
the compressor and condenser fan are
operating, the temperature control and defrost
control are OK.
3.
Orange wire open on neutral side of
evaporator fan.
Refer to Schematics.
Light Does Not Illuminate
Check for the following problems:
1.
Lamp faulty.
2.
Door switch open.
Check continuity across
the door switch with the wires disconnected.
3.
Open wire or faulty connector.
Refer to
Schematics.
Defrost System Check (Freezer)
The automatic defrost function is controlled by the
defrost control. The defrost control contains a
motor/cam mechanism that switches the defrost
control between defrost mode and cooling mode.
The defrost control motor/cam mechanism
operates only when the temperature control
(switch) is closed. After 8 hours of motor/cam
mechanism runtime in cooling mode, the defrost
control switches to defrost mode. The defrost
control will stay in defrost mode, providing
115 VAC to the heater for 30 minutes of motor/cam
mechanism runtime. The defrost thermostat
switch is mounted on the evaporator and, when
closed, completes the neutral side of the defrost
heater circuit. The defrost thermostat switch
opens when the evaporator temperature raises to
58 °F and closes when the evaporator
temperature lowers to 28 °F. The defrost
thermostat switch typically opens during the
defrost cycle, preventing the heater from
defrosting for the full 30 minutes. The purpose for
the 30-minute defrost mode at the defrost control
is to prevent the compressor from operating and
refreezing any water that may be dripping from the
evaporator.
Check for the following problems:
1.
Defrost heater open.
Check resistance
across the defrost heater. Refer to Schematics
for resistance values.
2.
Defrost thermostat switch stuck open.
The
defrost thermostat switch opens when the
evaporator temperature raises to 58 °F and
closes when the evaporator temperature
lowers to 28 °F.
3.
Defrost control open in defrost mode.
Manually rotate the defrost control into defrost
mode. Check for continuity across the defrost
control between terminals 2 and 3. Refer to
Schematics.
4.
Open wire or faulty connector.
Refer to
Schematics.
5.
Clogged or frozen drain
. Check for a
clogged or frozen drain. If frozen, see Heat
conducting clip not installed below.
6.
Heat conducting clip not installed
. If the
heat conducting clip is not installed on the
evaporator and in the drain, the drain may
freeze closed.
