Electrolux Built-In Dishwasher, Service Manual

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cabinet temperature. There is a 10-minute dwell period
after the heater cycles off.
Note: Upon initial power-up, the fresh food and freezer
go into heated defrost simultaneously, after 4 hours of
accumulated compressor run time.
During unusual cooling situations where there are no door
openings (such as vacations), the time between heated
defrost cycles may increase. If the ambient room
temperature is above 82°F (28°C) and there are no door
openings, the fresh food defrost occurs every 8 hours, and
the freezer defrost occurs every 16 hours. If the ambient
room temperature is below 82°F (28°C), defrost occurs at
the normal intervals – fresh food defrost every 5 hours
and freezer defrost every 10 hours of accumulated
compressor run time.
Thermistor Error Defrost Operation
If either evaporator thermistor fails (open or shorted), the
power control board (PCB) defaults to a timed defrost
cycle based on cabinet temperature.
If the freezer evaporator thermistor fails (open or shorted)
and the freezer temperature is below 27°F (-3°C), the
freezer defrost heater will be energized for 20 minutes. If
the freezer temperature is above 27°F (-3°C), the heater
will not come on.
If the fresh food evaporator thermistor fails (open or
shorted) and the fresh food temperature is below 68°F
(20°C), the fresh food defrost heater will be energized for
10 minutes. If the fresh food temperature is above 68°F
(20°C), the heater will not come on.
During thermistor error operation, the control defaults to
fresh food defrost every 5 hours and freezer defrost every
10 hours of accumulated compressor run time.
Fans
All 3 fans (condenser, freezer, and fresh food) are
variable-speed DC fans. The speed of each fan is
controlled by an algorithm in the power control board
(PCB) and determined by many factors, such as room
ambient, thermal load, temperature settings, number of
door openings, etc. The fans are extremely QUIET, and
determining fan speed is very diffi cult. As a general rule,
if the voltage measured at the fan is within limits and airfl
ow is felt through the vents, assume the fans are working
correctly.
Note: The fans will run on a 9-volt battery for testing
purposes. Use the two higher voltage pins as described in
the following procedures.
Freezer Evaporator Fan
The freezer fan assembly is mounted directly to the
freezer evaporator. The fan assembly (motor, blower and
housing) is available as a separate part or complete and
preassembled on a new freezer evaporator.
Operation of the freezer fan is also affected by room
temperature. If the ambient thermistor senses a
temperature of 82°F (28°C) or higher, the freezer fan will
delay 5 minutes (after the compressor has started) before
starting and circulating the freezer air. Below 82°F
(28°C), the fan will start immediately with the
compressor.
The freezer evaporator fan motor supply voltage can be
checked at CN06 on the terminal block.
When the power control board (PCB) is energizing the
fan, check for approximately 8 to11 VDC at CN06,
between pin #2 and pin #3, and approximately 2.25 VDC,
between pin #1 and pin #3 .
Fresh Food Evaporator Fan
The fresh food fan assembly is mounted directly to the
fresh food evaporator. The fan assembly (motor, blower,
and housing) is available as a separate part or complete
and preassembled on a new fresh food evaporator.
The fresh food evaporator fan motor supply voltage can
be checked at CN05 on the terminal block. When the
power control board (PCB) is energizing the fan, check
for approximately 7 to 8 VDC between pin #2 and pin #6,
and approximately 2 VDC between pin #2 and pin #5
at CN05.
Condenser Fan Assembly
Ambient temperature affects the operation of the
condenser fan. If the room temperature is less than 45°F
(7°C), the condenser fan will not run when the
compressor is on. If the temperature is between 45°F (7°C)