Troubleshooting; Safety Limits - Manitowoc S300 Technician's Handbook

Safety Limits

In addition to standard safety controls, the control
board has built in safety limit controls which protect the
ice machine from major component failures.
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.
3. Watch the safety limit lights/harvest light on the
control board. If a safety limit has been recorded,
the corresponding light will flash once, twice or
three times to indicate which safety limit stopped
the ice machine.
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 all models - 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 500 consecutive 3.5 minute harvest
cycles occur, the ice machine stops.
• Safety Limit 2 quad 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 quad 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 harvest
light.
Part Number 80-1479-3 7/10

Troubleshooting

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