Section 4Ice Machine Sequence of Operation4-2HARVEST SEQUENCE5. Water PurgeThe water pump continues to run and the water dumpvalve energizes for 45 seconds, to purge the water inthe sump trough. After the 45 second water purge, thewater pump and dump valve de-energize. The hot gasvalve(s) also opens at the beginning of the waterpurge, to divert hot refrigerant gas into theevaporator.New style circuit boards have an adjustable waterpurge in the harvest cycle. This permits a 0 (off), 15,30 or 45 second purge cycle.6. HarvestThe hot gas valve(s) remains open and the refrigerantgas warms the evaporator causing the cubes to slide,as a sheet, off the evaporator and into the storage bin.The sliding sheet of cubes swings the water curtainout, opening the bin switch. The momentary openingand re-closing of the bin switch terminates theharvest sequence and returns the ice machine to thefreeze sequence (Step 3 - 4.)Harvest Sequence (Typical J450 Shown)AUTOMATIC SHUT-OFF7. Automatic Shut-OffWhen the storage bin is full at the end of a harvestsequence, the sheet of cubes fails to clear the watercurtain and will hold it open. After the water curtainis held open for 7 seconds, the ice machine shuts off.The ice machine remains off for 3 minutes before itcan automatically restart.The ice machine remains off until enough ice hasbeen removed from the storage bin to allow the ice tofall clear of the water curtain. As the water curtainswings back to the operating position, the bin switchre-closes and the ice machine restarts (steps 1 - 2),provided the 3 minute delay period is complete.Automatic Shut-Off (Typical J450 Shown)
