R-Pro › Field cases › Refrigeration systems
Thermostat / Controller Failure
Likely causes
Setpoint higher than cabinet temperature (no demand)
Check: Confirm setpoint is lower than current cabinet temperature
What to do: Confirm setpoint is lower than current cabinet temperature → Measure output voltage at control terminal → Verify sensor bulb is correctly positioned → Bridge control terminals; if compressor starts, thermostat is faulty → Replace with same specification thermostat
Sensor bulb damaged or sensing tube gas leak
Check: Measure output voltage at control terminal
What to do: Measure output voltage at control terminal → Verify sensor bulb is correctly positioned → Bridge control terminals; if compressor starts, thermostat is faulty → Replace with same specification thermostat
Internal contact failure
Check: Verify sensor bulb is correctly positioned
What to do: Verify sensor bulb is correctly positioned → Bridge control terminals; if compressor starts, thermostat is faulty → Replace with same specification thermostat
Thermostat is not outputting a start signal. Check temperature settings, then replace if confirmed faulty.
All 565 cases work offline in R-Pro, with error codes for 62 brands and P-T data for 108 refrigerants.
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