86 Part Number STH038 5/12
SAFETY LIMIT #1
Freeze time exceeds 60 minutes for 6 consecutive
freeze cycles.
Possible cause list
Water System
• Loss of water from sump area
• Low water pressure 1.37 bar min (20 psig)
• High water pressure 5.51 bar max (80 psig)
• High water temperature 32°C max (90°F)
• Clogged water distribution tube
• Dirty/defective water fill valve
• Dirty/defective water dump valve
• Defective water pump
• Dirty/defective water level probe
Electrical System
• Low incoming voltage
• Ice thickness probe out of adjustment
• Harvest cycle not initiated electrically
• Contactor not energizing
• Compressor electrically non-operational
• Defective fan cycling control
• Defective fan motor
Miscellaneous
• High inlet air temperature
• Condenser discharge air recirculation
• Restricted air flow/dirty condenser fins
• Defective harvest valve
• Non-Manitowoc components
• Improper refrigerant charge
• Defective compressor
• TXV starving or flooding (check bulb mounting)
• Non-condensable in refrigeration system
• Plugged or restricted high side refrigerant lines or
component