High Pressure Cutout (Hpco) Control - Koolaire KDT0300A Technician's Handbook

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: 600 psig ±10 4137 kPa
Cut-in: 450 psig ±10 3103 kPa
(Must be below 450 psig - 3103 kPa to reset).
Check Procedure
1. Move toggle switch to OFF.
2. Connect manifold gauge.
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 models, disconnect the fan motor.
5. Move toggle switch to ON.
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.
If discharge pressure exceeds 600 psig - 4137 kPa and
the HPCO control does not cut out, cycle the toggle
switch Off to stop ice machine operation.
Replace the HPCO control if it:
• Will not reset (below 450 psig - 3103 kPa)
• Does not open at the specified cut-out point
Part Number STH063 9/17
±10
±10
Warning
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