ELECTRICAL SEQUENCE
Refer the wiring diagram as needed.
Each system is separate
If the machine is switched off at the master
switch, but is otherwise ready to go, switching
the master switch to on and pressing the start
reset switch does the following:
••
The bin empty light on the circuit board
goes on
••
There is a 15 second delay
••
If there is enough water in the reservoir, the
circuit board will allow the machine to start
up.
Start up consists of:
••
The liquid line relay and auger motor relay
become energized, connecting power to the
windings of the auger motor.
••
The auger motor starts, and the centrifugal
switch closes, connecting power to the
liquid line valve coil.
••
The liquid line valve opens, and the
refrigerant flows to the thermostatic
expansion valve and into the evpaorator.
••
As ice goes past the ice level sensors, the
bin empty light will stay on, and the
machine will continue to run, unless the ice
stays between the sensors for more than
15 seconds (bin full). At that point, the bin
empty light goes out, and the machine
shuts down.
Shut Down consists of:
••
The liquid line relay opens.
••
The liquid line valve closes
••
Ice making stops
••
The auger motor is run by the circuit board
for 2.5 more minutes, clearing out ice in the
evaporator, and then
••
The auger motor relay opens, and the
auger motor stops.
If the ice level sensor is clear (bin empty) for
more than 15 seconds, the machine will start
up again.
Another purpose of the circuit board is to turn
the machine off if there is not enough water in
the machine.
••
When the water level in the reservoir falls
below the water level sensor, the machine
will "shut down"
••
When the water refills the reservoir, the
machine will start up again.
Separate from the circuit board:
••
If the spout switch opens, the machine will
stop immediately (through the relays on the
circuit board). It must be manually reset at
the reset switch.
••
The master switch is the manual control for
each system, but it is not a service
disconnect.
NM1852RH
August 1992
Page 11
