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4.17 PC Troubleshooting
4.17.1 Digital display output
4.17.2 Description
▪ Water side heat exchanger low pressure protection.
▪ All units stop running.
▪ Error code is displayed on main PCB and user interface.
4.17.3 Possible causes
▪ Low pressure switch not connected properly or has malfunctioned.
▪ Insufficient refrigerant.
▪ Low pressure side blockage.
▪ Poor evaporator heat exchange in heating mode.
▪ Insufficient water flow in cooling mode.
▪ Main PCB damaged.