Safety Timers; Safety Limits; Warm Water Rinse Cycle - Manitowoc S Installation, Use & Care Manual

Ice Machine Operation

SAFETY TIMERS

The control board has the following non-adjustable
safety timers:
• The ice machine is locked into the freeze cycle for 6
minutes before a harvest cycle can be initiated.
Freeze lock is bypassed after moving the toggle
switch from OFF to ICE position for the first cycle
only.
• The maximum freeze time is 60 minutes at which
time the control board automatically initiates a
harvest sequence (steps 5 & 6).
• The maximum harvest time is 3.5 minutes for single
evaporators and 7 minutes for multiple evaporator
model. The control board automatically initiates a
freeze sequence (steps 3 & 4) when these times are
exceeded.

SAFETY LIMITS

Safety limits are stored and indicated by the control
board after three cycles. The number of cycles required
to stop the ice machine varies for each safety limit.
• Safety Limit 1 - If the freeze time reaches 60 minutes,
the control board automatically initiates a harvest
cycle. If 6 consecutive 60-minute freeze cycles occur,
the ice machine stops
• Safety Limit 2 single evaporator models - If the
harvest time reaches 3.5 minutes, the control board
automatically returns the ice machine to the freeze
cycle. If threeIf 500 consecutive 3.5 minute harvest
cycles occur, the ice machine stops.
• Safety Limit 2 multiple evaporator models - If the
harvest time reaches 7 minutes, the control board
automatically returns the ice machine to the freeze
cycle. If 500 consecutive 7 minute harvest cycles
occur, the ice machine stops.
• Safety Limit 3 multiple evaporator models - If the low
refrigerant pressure control opens, the ice machine
shuts off and starts a 5 minute delay period. If 3
consecutive low pressure events occur the ice
machine stops and flashes the safety/harvest light.
Use the following procedures to determine if the control
board contains a safety limit indication.
1. Move the toggle switch to OFF.
2. Move the toggle switch back to ICE. Watch the
safety limit lights on the control board. If a safety
limit has been recorded, the corresponding light will
blink once, twice or three times to indicate which
safety limit stopped the ice machine.
3-4

WARM WATER RINSE CYCLE

Single evaporator models only - Closing the back of the
evaporator allows ice to build up on the rear of the
evaporator and the plastic evaporator frame parts. After
200 freeze/harvest cycles have been completed the
control board will initiate a warm water rinse.
After the 200th harvest cycle ends:
• The Clean and Harvest LED's energize to indicate
the ice machine is in a warm water rinse.
• The compressor and harvest valve remain
energized.
• The water pump energizes.
• The water inlet valve energizes until water contacts
the water level probe.
• The compressor and harvest valve warm the water
for 5 minutes, then de-energize.
• The water pump remains energized for an additional
5 minutes (10 minute total on time) then de-
energizes.
NOTE:
The warm water rinse cycle can be terminated by
moving the toggle switch to the OFF position, then back to ICE.
Section 3
Part Number 000000966 03/09