Service Manual
Table Of Contents
- Important Safety Information
- I. Specifications
- II. General Information
- III. Technical Data
- IV. Service Diagnosis
- V. Replacement of Components
- VI. Maintenance
- VII. Disposal
20
E. Compressor Protector, Short Cycle Protection, and High-Pressure Switch
1. Compressor External or Internal Protector
If combined temperature/amperage value is above the limit specied by the compressor
manufacturer, the compressor external or internal protector operates independently to
turn off the compressor. The compressor external or internal protector de-energizes the
compressor until the temperature/amperage value returns to an acceptable level.
• If the condenser fan motor is operating and the compressor is off, it is most likely that
the compressor external or internal protector opened. If both the compressor and
condenser fan motor are off, it is most likely the appliance is off or the high-pressure
switch has opened. For further details, see "IV. Service Diagnosis."
• On refrigerators, the compressor external protector is integrated with the start relay.
On 1-section freezers, the compressor protector is an internal protector. On 2-section
freezers, the compressor protector is an external protector.
2. Short-Cycle Protection
There is a 2-minute minimum off-time and on-time for the compressor.
Note: Time may vary with compressor protector or high-pressure switch activation.
3. High-Pressure Switch
If pressure on the high-side of the appliance exceeds Hoshizaki specications, the
high-pressure switch activates and interrupts the compressor circuit, de-energizing the
compressor until the pressure returns to an acceptable level.
F. Mullion/Perimeter Heater
Refrigerators and freezers with mullions are equipped with mullion heaters. Freezers are
also equipped with perimeter heaters. The heaters are energized as soon as the power
switch is turned on.
G. Thermistors
The cabinet thermistor is used for cabinet temperature control and the defrost thermistor
is used for defrost cycle initiation and termination. Thermistor resistance varies
depending on temperature. The control module monitors the resistance to control system
operation. No adjustment is required. For further details, see "IV.C. Thermistor Check."