Whirlpool KUIA18NNJ*11 Ice Maker User Manual


 
3-5
OPERATIONAL MODES
There are four main operational modes for the
ice maker (more detailed operation is found in
the ow chart on page 6-5):
• Freeze
• Harvest
• Clean
• Service (Diagnostics)
ICE MAKING CYCLE
In addition, there are three possible “Off” cycles
for the ice maker. They occur when:
1. The bin is full of ice and the LED is il-
luminated “ON/OFF” (Idle mode).
2. The "On/OFF” control switch has been
held for three seconds. The ON/OFF
LED will go out.
3. The Holiday Mode.
Electrical System
Line Voltage is supplied to the electrical control
switches and the primary side of the step-down
dual transformer. The dual transformer reduces
120 VAC to 8.75 VAC for the cutter grid and
the bin light and 12 VAC for the drain and recir-
culating pumps. The electronic control board
directs 12 VAC to the water recirculating and
reservoir drain pumps, and 120 VAC to the
hot gas solenoid, condenser fan motor, and
compressor. The measured ll water valve will
always have 120 VAC on the BK and WH wires
and 14 VDC on the OR/WH and BK/RD wires.
An evaporator thermistor supplies temperature
information to the electronic control to determine
when to terminate the harvest cycle.
Refrigeration System
The hot gas refrigerant, under high pressure, is
forced through the condenser, where it changes
into a liquid, and ows through the drier and
capillary tube into the evaporator. Under low
pressure in the evaporator, the liquid refrigerant
absorbs heat from the water owing over the
evaporator as the refrigerant evaporates into
a gas. As a low pressure gas, the refrigerant
ows back through the suction line of the heat
exchanger, to the compressor.
During the Freeze mode, some of the hot gas
that is in the condenser accumulating tube,
condenses to a liquid, and remains in the ac-
cumulating tube.
During the later stages of the Freeze mode, as
the ice slab forms on the evaporator freezing
plate, some of the refrigerant passing through
the evaporator will not evaporate into a gas, but
will remain a liquid. This liquid refrigerant will
settle in the accumulator, while the refrigerant
vapor is sucked off through the suction tube at
the top of the accumulator. This accumulated
liquid refrigerant will eventually be directed to
the evaporator to quickly warm the evaporator
plate during the Harvest mode.
NOTE: It is very important that the accumulator
is not tilted out of a horizontal position. If moved,
it could cause compressor failure.
Water System
The water recirculating pump moves the water
from the reservoir pan up to the distributor,
where it ows out over the evaporator freez-
ing plate.
Water that does not freeze on the evaporator
plate runs off the front edge, and falls back into
the reservoir, where it is recirculated back to
the water distributor.
As the ice slab forms, the minerals in the water
are on the surface of the ice. The water ow-
ing over the top of the ice slab washes these
minerals back into the water reservoir pan. The
water continues to recirculate until the water
level in the reservoir drops to the bottom of the
water level sensor. When the water level in the
reservoir drops below the sensor, the control
terminates the freeze mode and initiates the
harvest mode.
The control signals the measured ll valve to ll
to the selected water level setting. The mea-
sured ll valve uses a ow meter to accurately ll
to the correct volume. Thin Ice uses 32 ounces
(954cc), Normal Ice 37 ounces (1106cc), and
Thick Ice 42.5 ounces (1258cc).