KitchenAid Kitchen Aid KAR-19 Technical Education page 18

HARVEST MODE
Electrical System
When the water level in the reservoir drops
below the water level sensor it signals the
electronic control to terminate power to the
condenser fan, and then the water recirculating
pump. The reservoir drain pump is activated
to fully drain the reservoir. Power is then sup-
plied to the hot gas valve and a fi ll request is
sent to the measured fi ll valve. The fi ll valve
fi lls to the requested volume while the hot gas
valve is energized for the balance of the har-
vest mode.
If the evaporator thermistor is unplugged, the
evaporator defaults to a timed 4 minute har-
vest.
If the water level sensor is disconnected or
open, the control defaults to 25 minutes of
freeze time. The cleaning indicator LED fea-
ture will not function if the water level sensor
is disconnected.
Refrigeration System
The hot gas valve opens, allowing high pres-
sure refrigerant gas to bypass the condenser,
and fl ow through the condenser accumulating
tube. The hot gas pushes the liquid refrigerant
that has accumulated in the accumulator tube
up into the evaporator. The hot liquid refrigerant
evenly heats the evaporator plate so that the
ice slab releases quickly and evenly.
The ice slab, when released, slides off of the
evaporator plate onto the cutter grid.
Water System
The electronic control board sends a signal to
the water valve. The signal tells the water valve
how much water to be fi lled, allowing water to
fl ow into the water reservoir pan. The water
fi ll volume is determined by the ice thickness
setting.
As a result of the hot gas fl ow and the ice sliding
off the evaporator plate, the evaporator tem-
perature begins to rise. When the evaporator
thermistor reaches the set temperature (52°F),
the unit switches to the Freeze mode. This cy-
cling between Freeze and Harvest, continues
until the ice bin is full.
The electronic control board operates the vari-
ous components and systems in the ice maker
for each of the Freeze and Harvest modes.
CLEAN MODE
Electrical System
The electronic control board operates the
various components and systems during the
Clean mode.
For the order of the components cycled, see
the fl ow chart on page 6-13.
Water System
When the service control switch is in the "Clean"
position, the water recirculating pump circulates
the cleaning solution that has been added to the
reservoir, up to the water distributor, across the
evaporator, and back into the reservoir, where
it is recirculated. The compressor and hot gas
valve operate to heat the evaporator.
DIAGNOSTIC MODE
1. Do not continue with the diagnosis of the ice
maker if a fuse is blown, a circuit breaker
is tripped, or if there is less than a 120 volt
power supply at the wall outlet.
2. All units that have failed during the fi rst few
days of use should be checked for loose
connections or miswiring.
Entering and Navigating — Manual
Diagnostics
• Turn the product on. Within 10 seconds of
Power On, press and hold the On and the
Clean buttons. Release both buttons when
all user interface LEDs begin to fl ash.
• Within 5 seconds of all LEDs fl ashing, push
any other button on the user interface. This
begins manual diagnostics.
• If no button is pressed within 5 seconds, the
product goes into the automatic diagnostic
mode used at the assembly plant. Each
component is cycled for 5 seconds.
• The Service button (or Off button on some
models) is used to advance through each
step.
• To exit manual diagnostics, press the Power
button (or On button on some models)
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