Manitowoc Ice Q 1800 Ice Maker User Manual


 
43
Refrigeration System
Pressure Control Specifications and Diagnostics
HIGH PRESSURE CUTOUT
(HPCO) CONTROL
Function
Stops the ice machine if subjected to excessive
high-side pressure.
The HPCO control is normally closed, and opens on
a rise in discharge pressure.
Specifications
Cut-out: 450 psig ±10
Cut-in: Manual or automatic reset
(Must be below 300 psig to reset).
Check Procedure
1. Set ICE/OFF/CLEAN switch to OFF, (Manual
reset HPCO reset if tripped).
2. Connect manifold gauges.
3. Hook voltmeter in parallel across the HPCO,
leaving wires attached.
4. On water-cooled models, close the water service
valve to the water condenser inlet. On self-
contained air-cooled and remote models,
disconnect the fan motor.
5. Set ICE/OFF/CLEAN switch to ICE.
6. No water or air flowing through the condenser
will cause the HPCO control to open because of
excessive pressure. Watch the pressure gauge
and record the cut-out pressure.
WARNING
If discharge pressure exceeds 460 psig and the
HPCO control does not cut out, set
ICE/OFF/CLEAN switch to OFF to stop ice
machine operation.
Replace the HPCO control if it:
Will not reset (below 300 psig)
Does not open at the specified cut-out point