Electrical Component Details - continued
Hot Gas Valve
•
Operated by the controller in parallel with the harvest assist solenoid. Cycles on and off at the
beginning of a restart. Energized throughout the harvest cycle. Line voltage coil.
Controller
•
Senses ice thickness, water conductivity, water temperature, discharge temperature. Controls
compressor contactor, fan motor, water pump, hot gas valve, purge valve, harvest assist solenoid.
Indicates status and component operation. 12 volt.
Transformer
•
12 volt secondary, supplies power to controller only.
Water Sensor
•
Three probe conductivity sensor. Used for WaterSense system.
Ice Thickness Sensor
•
Single wire conductivity sensor. Circuit made from controller to ground to controller when water
contacts a probe suspended over ice plate. Signals ready for harvest.
Curtain Switch
•
Magnetic reed switch. Normally open, switch is closed when magnet is nearby. Switch can be
connected to either J8 or J7 of controller. Curtain may be removed in the freeze cycle without
affecting controller operation. Curtain removed during harvest will cause the controller to terminate
harvest and shut the unit off.
Water temperature sensor
•
Thermistor inserted into the water pump discharge hose. Reported temperature used by the
controller to determine anti-slush cycle start time.
Discharge temperature sensor.
•
Thermistor attached to the discharge line near the compressor. Reported temperature used by the
controller to determine end-of-cycle-fan-off-delay time. If discharge temperature exceeds a preset
maximum, controller will shut the machine off.
Note: Controller will operate machine in a default mode with thermistors disconnected from the controller.
Diagnostic code #5 or 7 will be displayed during that time.
May 2008
Page 21
CU1526, CU2026, CU3030
Service Manual