Manitowoc Ice STH003 Ice Maker User Manual


 
39
ICE MAKING SEQUENCE OF
OPERATION
Depending on ambient conditions and cold water
supply temperature, the ice making process will take
approximately 30 minutes.
1. Initial Start-Up or Start-Up After Automatic
Shut-Off — Water Fill
Before the compressor starts, the water inlet valve
will energize to purge old water from the system
for about 3 minutes.
2. Refrigeration System Start-Up
The compressor starts after the Water Fill cycle
and remains on throughout the Freeze and
Harvest cycles. The condenser fan motor starts
and runs throughout the Freeze cycle.
3. Freeze
The water pump sprays water into the inverted
cups. The water freezes layer by layer, until an ice
cube forms in each cup. The control system will
adjust the length of the Freeze cycle to conditions.
4. Harvest
The water pump shuts off and the water inlet valve
starts up to assist harvest and refill the water
sump. The evaporator is warmed, allowing the
cubes to release from the evaporator and drop into
the storage bin. The control system will adjust the
length of the Harvest cycle to conditions and
regulate whether the condenser fan will run.
At the end of the Harvest cycle, the ice machine
will start another Freeze cycle (Step 3).
5. Automatic Shut-Off
The level of ice in the storage bin controls the ice
machine shut-off. When the bin is full, ice will
contact the bin thermostat bulb holder. The bin
thermostat bulb cools, which stops the ice
machine. The ice machine remains off until ice no
longer contacts the bin thermostat bulb holder and
the thermostat bulb warms up. The increase in
temperature will restart the ice machine (step 1).