Product Manual, Issue 8 CMS100
www.nexo.comPage 40
5.5 Condenser Sensor Alarms
The controller has detected an open circuit on the condenser input, please check:
` The condenser sensor is properly connected to the condenser input on the controller
` The condenser sensor is reading the correct temperature – Temperature versus resistance:
Thermistor is Negative Temperature Coecient (NTC)
` The condenser input on the controller is in working order – The controller should not register
a PF2 alarm when a known working condenser sensor is connected
5.6 Freeze-up protection (888)
Problems with freeze-up protection may occur if the ambient temperature falls below 0°C (32°F) or if the
appliance sensor fails.
The controller has detected a below nominal temperature for the cabinet, please check:
` The appliance sensor is properly connected to the appliance input on the controller
` The correct positioning of the appliance sensor
` An adequate DTT parameter setting has been selected (when taking into account the cabinets
temperature settings)
` The appliance sensor is reading the correct temperature – Temperature versus resistance:
Thermistor is Negative Temperature Coecient (NTC)
` The appliance input on the controller is in working order – The controller should register a PF1
alarm when the appliance sensor is not connected
5.7 Condenser high temperature (Ht) alarms
Condenser high temperature (Ht) alarms alert to problems with the refrigeration system such as a blocked
condenser or faulty condenser fan.
The controller has detected an above nominal temperature for the condenser, please check:
` Adequate airow through condenser – Condenser grill is free from obstructions
` Condenser fan operation
` Evaporator for excessive freeze up
` An adequate HT parameter setting has been selected (when taking into account the ambient
temperature)
` If there is Refrigeration System leakage