Electrical Sequence - Remote Cooled - Scotsman C2648 - SERVICE MANUAL 11-2010 Service Manual

C2648 Service Manual

Electrical Sequence - Remote Cooled

Power connected, unit previously switched Off.
Control board does a self check. If the self check fails, the unit displays an E and no further action will
occur.
If the self check passes, the controller will display a 0, the curtain lights will be ON and the Power and
Sump Empty lights will be ON.
Pushing and releasing the On button will start the ice making process.
The display will begin to blink F. The component indicator lights will switch on and off to match the
following process:
The purge valve opens and one water pump starts to empty the reservoir. This is done to discharge any
excess water from ice melting into the reservoir.
The hot gas valves and the harvest assist solenoids are energized by the High Capacity Relay.
The inlet water valve will open to fill the reservoir. The water valve can open any time the water level is
low.
After a few seconds the purge valve closes and the pump shuts off.
When the reservoir is full the inlet water valve stops, the liquid line valve is opened and the compressor
switches on. Five seconds after the compressor starts the hot gas valve and the harvest assist solenoid
are de-energized. Both water pumps switch on.
Light Information: The display shows a non-blinking F. The Power and Status Lights will be Green. The
compressor, fan motor, water pump, sump full lights will be ON and all curtain switch lights will be OFF.
The Freeze cycle continues. When the reservoir water temperature falls to a certain preset point, the
water pumps will shut off for 30 seconds. This is the anti-slush period. At this time the controller checks
the conductivity of the water in the reservoir for the auto-purge feature. After the water pumps restart the
Sump Full light will go out and neither sump lights will be on for the rest of the freeze cycle.
When the ice has built up enough so that the water flowing over the evaporator comes into continuous
contact with the ice level sensor, the Ready to Harvest light will begin to blink on and off. When it has
been On continuously for 3 seconds, the controller will switch the machine into a Harvest cycle.
Indicator Information: The display shows a non-blinking H. The Power and Status Lights will be Green.
The compressor and hot gas valve lights will be ON. After a few seconds the water pump, purge valve
and inlet water valve lights will switch on.
The three harvest assist solenoids are connected in parallel with the three hot gas valves. Although
energized throughout the harvest cycle, a harvest assist piston does not move until the ice has become
partially loosened from the evaporator plate by the action of the hot refrigerant gas passing through the
evaporator serpentine.
November 2010
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