Manitowoc Marine Q 1000, Service Technician'S Handbook

Page: 93 / 179

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Refrigeration System
•
Non-Manitowoc components
•
Improper refrigerant charge
•
Defective head pressure control (remotes)
•
Defective harvest valve
•
Defective compressor
•
TXV starving or flooding (check bulb mounting)
•
Non-condensable in refrigeration system
•
Plugged or restricted high side refrigerant lines or
component
Safety Limit #2
Refer to page 75 for control board identification and
safety limit operation.
Control Board with Black Microprocessor - Harvest
time exceeds 3.5 minutes for 3 consecutive harvest
cycles.
or
Control Board with Orange Label on
Microprocessor - Harvest time exceeds 3.5 minutes
for 500 consecutive harvest cycles.
Possible Cause Checklist
Improper Installation
•
Refer to “Installation/Visual Inspection Checklist”
Water System
•
Water area (evaporator) dirty
•
Dirty/defective water dump valve
•
Vent tube not installed on water outlet drain
•
Water freezing behind evaporator
•
Plastic extrusions and gaskets not securely
mounted to the evaporator
•
Low water pressure (20 psig min.)
•
Loss of water from sump area
•
Clogged water distribution tube
•
Dirty/defective water fill valve
•
Defective water pump