Freeze; Harvest - GE Electronic Icemaker Technical Service Manual

The feeler arm moves horizontally. A full
ice bucket will prevent the arm from moving out
to the fully extended position, stopping the next
harvest cycle until ice cubes are removed and
the arm is able to swing out completely
The thermistor is mounted in the mold body,
directly behind the control housing. The
thermistor provides two functions: to measure
the ice temperature during freezing and for
water level detection during fill.
THERMISTOR
The normal icemaker sequence is to fill the
mold with water, wait until the water is frozen,
harvest the ice and then repeat the cycle. To
accomplish this, three cycles are programmed
in the electronic control: Freeze, Harvest and
Water Fill. The control also contains a Power-
On Diagnostic Test mode, a Harvest Fix mode,
a Fault mode and a Service Diagnostic Test
mode.
FEELER ARM
FULLY EXTENDED

Freeze

The "Freeze" cycle is the period where
the icemaker is waiting for the cubes to freeze
solid. This period of time is based on an
algorithm programmed into the electronic
control. The control makes these calculations
once per second and takes into account the
thermistors current resistance value and the
rate of resistance change. As a result, freeze
times vary based on refrigerator control settings
and environmental conditions (door openings,
room temperature, etc.) but average
approximately 75 minutes for each drop of 7
ice cubes.

Harvest

The "Harvest" cycle will begin when the
freeze algorithm has been satisfied and the arm
is in the "out" or "fully extended" position. If the
arm is in the "in" position when harvest is to
begin, a delay of 3 minutes will be added once
the arm moves to the extended position. This
3 minute delay allows drawer type ice buckets
to be removed for up to 3 minutes without
starting a harvest. The 3 minute delay will begin
again if the arm goes back to the "in" position
anytime during the delay period. The arm is
spring loaded and will go to the out position
unless it is being held in position by an obstacle
such as an ice cube.
At the start of the harvest cycle, the mold heater
will be turned on. One second later, the motor
will start. The heater will remain on until the
mold temperature is above 35.6°F (2°C) and a
2
SPRING
PHILLIPS
SCREW