Manitowoc

OperationQM45/Q130/Q170/Q210/Q270INITIAL START-UP OR START-UP AFTERAUTOMATIC SHUT-OFF1. Pressure EqualizationBefore the compressor starts the hot gas valve isenergized for 15 seconds to equalize pressures duringthe initial refrigeration system start-up.2. Refrigeration System Start-upThe compressor starts after the 15-second pressureequalization, and remains on throughout the entireFreeze and Harvest Sequences. The hot gas valveremains on for 5 seconds during initial compressorstart-up and then shuts off.At the same time the compressor starts, thecondenser fan motor (air-cooled models) is suppliedwith power throughout the entire Freeze and HarvestSequences. The fan motor is wired through a fan cyclepressure control, therefore it may cycle on and off.(The compressor and condenser fan motor are wiredthrough the relay. As a result, any time the relay coil isenergized, the compressor and fan motor are suppliedwith power.)FREEZE SEQUENCE3. PrechillThe compressor is on for 30 seconds prior to waterflow to prechill the evaporator.4. FreezeThe water pump starts after the 30-second prechill. Aneven flow of water is directed across the evaporatorand into each cube cell, where it freezes.When sufficient ice has formed, the water flow (not theice) contacts the ice thickness probe. Afterapproximately 7 seconds of continual water contact,the Harvest Sequence is initiated. The ice machinecannot initiate a Harvest Sequence until a 6-minutefreeze time has been surpassed.Part Number 80-01111-9 7/10 79