Ice-O-Matic ICE250 through ICE2100 SERIES - Manual (Page 19)

ICE Series How the ICE Machine Works
Page 14
How the ICE Machine Works
A general description of how the ICE Series cubers work is given below. With the ICE/OFF/WASH switch in the ICE
position, the compressor, water pump and condenser fan motor (when applicable) will energize starting the freeze
cycle.
During the freeze cycle, water is circulated over the evaporator(s) where the ice cubes are formed. When the suction
pressure has pulled down to the proper cut-in pressure of the timer initiate (pressure control), the contacts will close
and energize the time delay module (timer). At this time the cubes will be close to completion.
The remaining portion of the freeze cycle is determined by the timer setting. The timer is pre-set at the factory to
achieve the proper ice bridge thickness but may need to be adjusted upon initial start-up, see Page 15 for timer
adjustment.
Once the amount of time on the timer has passed, the control relay will be energized and the machine will enter
harvest. Power is now supplied to the water purge valve, hot gas valve, and the harvest motor.
The water purge valve opens, and allows the water pump to purge the water remaining in the water trough, removing
impurities and sediment. This allows the machine to produce clear ice cubes and keep mineral build up at a minimum.
The hot gas solenoid opens allowing hot gas to go directly to the evaporator, heating the evaporator and breaking the
bond between the evaporator and the ice slab.
The harvest assist motor, which is also energized during harvest, turns a slip clutch, which pushes a probe against the
back of the ice slab. Once the evaporator has reached approximately 40
°F (4.5°F) in temperature, the slip clutch
overcomes the bonding of the ice to the evaporator and pushes the slab of ice off of the evaporator and into the
storage bin.
The clutch also actuates a switch that rides on the outer edge of the clutch. When the clutch completes one
revolution, the switch is tripped and the machine enters the next freeze cycle.
When ice drops into a full bin during harvest, the splash curtain is held open which activates a bin switch shutting the
machine off. When ice is removed from the bin, the splash curtain will close and the machine will come back on.
Note: The ICEU150, 220, 225, 226, ICEU300 and 305 do not have a splash curtain. These models utilize a
thermostatic bin control in place of a mechanical bin switch.