Manitowoc Ice S Model S1000M Ice Maker User Manual


 
Refrigeration System Section 7
7-18
Part Number 80-1559-3
Pressure Control Specifications and
Diagnostics
HIGH PRESSURE CUT-OUT (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 (3103 kPa ±69, 31 Bar ±.69)
Cut-in: Manual or automatic reset
Must be below 300 psig (2068 kPa, 20.68
Bar ±.69) to reset
Check Procedure
1. Set ICE/OFF/CLEAN switch to OFF.
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.
Replace the HPCO control if it:
Will not reset [below 300 psig (2068 kPa, 20.68 Bar )]
Does not open at the specified cut-out point
!
Warning
If discharge pressure exceeds 460 psig (2068 kPa,
20.68 Bar ) and the HPCO control does not cut out,
set ICE/OFF/CLEAN switch to OFF to stop ice
machine operation.