Electrolux Built-In Dishwasher, Service Manual

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and testing between pin #2 (gray wire) and pin #3 (yellow
wire) on the harness.
Freezer Evaporator Thermistor
The evaporator thermistor is mounted in a copper sleeve
on the top, right corner of the evaporator. Check for
thermistor resistance (see
Thermistor Chart ) by
disconnecting the harness from CN06 and testing between
the pin #3 (gray wire) and pin #6 (red wire) on the
harness.
Fresh Food Evaporator Thermistor
The fresh food evaporator thermistor is mounted in a
sleeve on the left side of the evaporator. Check for
thermistor resistance (see
Thermistor Chart ) by
disconnecting the harness at CN05 and testing between
pin #2 (gray wire) and pin #4 (pink wire) on the harness.
Thermistor Emergency Operation
If the freezer thermistor opens (or shorts), the unit
defaults to the freezer evaporator thermistor. The
compressor and freezer fan cycle off when the freezer
evaporator temperature is -22°F (-30°C) or colder. The
compressor and freezer fan cycle on when the freezer
evaporator temperature is -2°F (-19°C) or warmer.
If the fresh food thermistor opens (or shorts), the fresh
food cooling operation defaults to the freezer thermistor.
Refrigerant will fl ow through the fresh food evaporator
any time the freezer evaporator is cooling. The fresh food
fan will cycle off once the fresh food evaporator
thermistor reaches 5°F (-15°C) or colder.
Defrost Cycles
The refrigerator incorporates two different methods of
defrost. Once the compressor has accumulated 2 hours of
compressor run time, and certain conditions are satisfi ed,
the fresh food evaporator goes through a “natural defrost”
cycle. In addition, at a specifi c time interval, both the
fresh food and freezer evaporators go through a “heated
defrost” cycle.
Natural Defrost (Fresh Food Only)
Once the fresh food temperature is satisfi ed, natural
defrost occurs on the fresh food evaporator, if the
following conditions have been met:
• The compressor has accumulated 2 hours of
run time.
• The ambient room temperature is above 66°F
(19°C).
• The freezer temperature is satisfied.
If the above conditions have been met, when the fresh
food temperature is satisfi ed, and the compressor cycles
off, the 3-way valve will open to both the fresh food and
freezer evaporators. This allows the refrigerant within the
system toequalize back through the evaporators. This
warm thermal mass (refrigerant) fl owing through the
evaporators helps to remove any frost buildup on the
fresh food evaporator (it has very little impact on the
freezer evaporator due to the freezer temperature). In
addition, when the fresh food evaporator thermistor is
below 23°F (-5°C), the fresh food evaporator fan will run
to help move air across the evaporator. Once the
thermistor reaches 28°F (-2°C), the fan will cycle off.
Note: If the compressor is still cooling the freezer section
when the fresh food cycles off, or the ambient room
temperature is below 66°F (19°C), natural defrost will not
occur.
Heated Defrost
In normal cooling operation (normal food load, door
openings, etc.), the power control board (PCB) will
energize the fresh food defrost heater every 5 hours of
compressor running time and the freezer defrost heater
every 10 hours of compressor running time. For example,
after approximately 10 accumulated hours of compressor
running time, the freezer evaporator will have gone
through one defrost cycle, and the fresh food evaporator
will have gone through two defrost cycles.
The fresh food heater cycles off when the fresh food
evaporator thermistor reaches 63°F (17°C). The freezer
heater cycles off when the freezer evaporator thermistor
reaches 68°F (20°C). The compressor and fans do not
operate when either section is defrosting, regardless of the