Manitowoc S model, Installation, Use & Care Manual

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Section 3 Ice Machine Operation
Part Number 000002477 3/08
3-5
HARVEST SEQUENCE
5. Water Purge
The air compressor (when used) and the harvest
valve(s) open at the beginning of the water purge to
divert refrigerant gas into the evaporator. The water
pump continues to run, and the water dump valve
energizes for 45 seconds to purge the water in the sump
trough. The water fill valve energizes for the last 15
seconds of the 45-second water purge.
After the 45 second water purge, the water fill valve,
water pump and dump valve de-energize. (Refer to
“Water Purge Adjustment” for details.)
When the refrigerant pressure is low enough to open the
fan cycling pressure control the condenser fan motor
stops.
* The IB0600C & S0600C ice machines do not use a
fan cycle control, therefore the condenser fan motor
will continue to run in the harvest cycle.
6. Harvest
The air compressor (when used) remains energized and
the harvest valve(s) remain open. The refrigerant gas
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 curtain out or ice
damper down, opening the bin switch.
The momentary opening and re-closing of the bin switch
terminates the harvest sequence and returns the ice
machine to the freeze sequence (steps 3-4).
S1470C/S1870C/S2170C Only
6A. Water Assist Harvest Feature
Typical duration of a Harvest sequence is less than 2.5
minutes. When the Harvest sequence time reaches 4
minutes, the following occurs:
4 minutes into a Harvest sequence: The water fill valve
will energize to fill the trough with water. 5 minutes into a
Harvest sequence: The water pump will energize and
flow water over the evaporators. The water fill valve and
water pump remain on until all bin switches have been
activated, or until the 7-minute Harvest sequence time
limit is reached.
AUTOMATIC SHUT-OFF
7. Automatic Shut-Off
Ice Machine Section: Shuts off when:
• The storage bin is full at the end of a harvest
sequence.
• The sheet of cubes fails to clear the water curtain
and hold it open.
• Ice damper is held down.
After the water curtain or ice damper are held open for
30 seconds, the ice machine shuts off. The ice machine
remains off for 3 minutes before it can automatically
restart.
CVD Condensing Unit: The liquid line solenoid valve
closes, allowing the refrigeration system to pump down.
When the refrigerant pressure is low enough to open the
fan cycling pressure control the condenser fan motor
stops. When the refrigerant pressure is low enough to
open the low pressure control, the contactor coil is de-
energized and the compressor stops.
The ice machine remains off until enough ice has been
removed from the storage bin to allow the ice to fall clear
of the water curtain or ice damper. As the water curtain
or ice damper swings back to the operating position, the
bin switch re-closes and the ice machine restarts (steps
1 - 2), provided the 3 minute delay period is complete.
* The IB0600C & S0600C ice machines do not use a
fan cycle control, therefore the condenser fan motor
will energize and de-energize with the compressor.