Troubleshooting - Emerson ZX User Manual

16.0 Trouble Shooting
With the Diagnostic Module, a technician is alerted to following type of conditions :
Discharge Line Temperature Overlimit
Ambient Sensor Failure
Mid Coil Temperature Sensor Failure
Discharge Line Temperature Thermistor Failure
High Pressure Cut Out
Compressor Over Current
Compressor Incorrect Phase Sequence
Compressor Voltage Imbalance
System Liquid Floodback
Troubleshooting for a ZX Condensing Unit is not very different form that for any other type of unit
except that with the feedback from the Diagnostic Module , the technician gets to the core of the
issues much quicker. These are CDU related conditions that can also give the technician some
idea about the condition of the system by using some basic refrigeration troubleshooting tables
( but not limited to these) as below with a basic gauge manifold :
D ischarge Pressure
S uction Pressure
Possible Causes/Effects
Low Refrigerant Shortage
Iced-up Evaporator
Low Superheat Setting at TXV
Restriction in Refrigeration system
High Front Seated Receiver Rotalock Valves
Lack of Ventilation around Unit
Refrigerant Overcharge
Presence of Non-Condensibles
High Ambient Temperatures
Low
Undersized Evaporator
Liquid Flashing in Liquid Line
High Oversized Evaporator
Excessive Airflow over Evaporator
Refrigerant Overcharge
48
Dirty Evaporator
Oversized Unit