Whirlpool R-106, Training Manual

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Water fill- At the end of the second revolution, an internal cam in the icemaker ener-
gizes a fill switch. The switch turns on the icemaker water valve and water is allowed
to enter the icemaker.
Terminate- Once filled with water, the icemaker cycle terminates. The icemaker is
now ready to repeat the cycle.
Electrical Operation
Ejector Blade Shut off Arm
Freeze cycle
Immediately after the icemaker fills with water, the freezer air begins to cools the ice
mold. Since the mold and water are essentially at the same temperature, the mold
thermostat will remain open until the ice and mold reach a predetermined temperature
(15°F, ±3°). Notice that the ejector blades are at approximately the 9:00 o’clock posi-
tion at the start of the cycle. This is known as the “home” position.
Thermostat Closes
When the mold and ice reach the set temperature, the thermostat closes. The mold
heater is energized through a parallel circuit which also energizes the motor.
First Three Seconds of Operation
All the while the icemaker is in the freeze cycle, the hold switch contact sits in a notch
on the icemaker cam. As soon as the motor begins to rotate the cam, the hold switch
contacts transfer and the switch closes. The hold switch contacts remain in this posi-
tion until the cam has traveled a full 360° and the switch contact falls into the notch
again.
At the same time, the feeler arm begins to raise. Since the shut-off switch is me-
chanically coupled to the feeler arm, movement of the arm causes the shut-off switch
contacts to transfer. The transfer of both these switches creates a parallel current
path for the mold heater and the icemaker motor. The heater begins to thaw the ice
in the mold and the motor advances the ejector blades until they come in contact with
the ice.
Blade Contacts Ice
Upon contacting the ice, the motor stalls since the mold heater has not had sufficient
time to melt the ice enough to free it from the mold. The heater continues to warm
the mold until the ice is free and the blades can dislodge the ice and continue their
sweep.
Once free of the mold, the ice loosens and the blades resume their rotation towards
the home position (9:00 o’clock). The ice is ejected.
Water Switch Closes
Just before the blades reach their home position, the cam closes the water fill switch
for approximately 7 seconds. Since the thermostat has not yet opened and is shunt-
ing the water valve solenoid, the water valve doesn’t open at this time.
Start of the Second Revolution
Once the cam reaches the home position, the hold switch momentarily goes back to
its normally closed position. While the mold has heated sufficiently to loosen the ice,
the mold has not yet reached the temperature required to open the mold thermostat.
The motor and heater continue to operate through the closed thermostat.