Control Board - KitchenAid KBFC42FS Technical Education

LOW VOLTAGE PHOENIX

CONTROL BOARD

A low voltage transformer, located on the left
side of the unit compartment, supplies 24 volts
ac to the Phoenix control board.
The Phoenix control provides the following
functions:
• Communicates with both ingredient care
center pans.
• Provides 24 volts dc to both ingredient care
center pans to operate the LED lighting in
each ingredient care center pan.
• Monitors a thermistor in each ingredient care
center pan.
• Controls the operation of the motorized air
baffle for each ingredient care center pan.
• Provides 24 volts dc to the heated flipper
mullion to prevent condensation on the flip-
per mullion.
• Communicates with the main electronic con-
trol. This includes the status of the refrigerator
door switches and evaporator fan motor.
The two controls communicate and work to-
gether to provide proper function. The Phoenix
control operates the ingredient care center
pan LED lighting and the mullion heater but it
does not get direct input on the position of the
refrigerator door switches. In order to operate
the LED pan lighting at the proper time, the
main control monitors the refrigerator door
switches and sends a communication on the
data line to let the Phoenix control know when
a refrigerator door is opened.
The Phoenix control supplies 24 volts dc to the
mullion heater when both refrigerator doors are
closed. When a refrigerator door is opened, or
an ingredient care center pan air door change
is needed, the output of the Phoenix control
board is switched from the mullion heater to
the ingredient care center pan.
Ingredient Care Center
Temperature Control
The control monitors the temperature of each
ingredient care center pan by means of a
thermistor located in the top of each pan.
When cooling is needed the Phoenix control
sends a request to the main control board to
operate the evaporator fan motor. The Phoenix
control board does not have direct control of
the evaporator fan motor. The Phoenix control
also sends a 12 vdc, peak to peak square wave
to the ingredient care center air door to open
the door.
The ingredient care center air door will be in
one of five possible positions based on the
ingredient care center user setting. The air
door will close at any setting when the proper
temperature has been reached. Here are the
four possible positions and temperatures for
each setting.
• Closed.
- When the refrigerator compartment is call-
ing for cooling and the freezer is satisfied.
This allows the refrigerator to cool faster.
- Any setting when proper pan temperature
has been achieved.
- When the refrigerator is in holiday mode.
- When the refrigerator is in defrost mode.
• Deli—40°F, open at a 10° angle.
• Produce—39°F, open at a 20° angle.
• Meats—33°F, open at a 30° angle.
• Quick Chill—25°F, open at a 45° angle.
When Quick Chill is selected, the pan
temperature is set to 25°F, and the freezer
temperature is set to –5°F, for one hour. The
evaporator fan motor operates and runs
at high speed until the set temperature is
reached. When the hour has timed out, the
ingredient care center user interface and
the freezer temperature both return to the
previous customer settings.
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