Installation Instructions

Appendix
0020147164_04 aroTHERM Installation instructions 49
Code Meaning Cause
F.537 High-pressure switch open – Coolant volume too high or too low
– Vacuum insufficient (10 mbar)
– Incondensable particle in the coolant circuit
– Pressure switch or electrical connection faulty
– Premature expansion in the liquid area of the coolant circuit (loss
of charge)
– Flow quantity too high (see defined maximum flow rate)
– Flow rate monitor faulty
– Insufficient heat transfer in the heat exchanger
F.539 Coolant pressure too low – Coolant quantity too low
– Air flow too low
– No thawing
– The resistance heating in the condensate receiver is faulty.
– 4-way valve faulty
– Electronic expansion valve motor faulty, or connection faulty
F.546 Sensor fault: High pressure – Faulty cabling
F.554 Coolant pressure not in operating range – Coolant volume too high or too low
– Incondensable particle in the coolant circuit
– Electronic expansion valve faulty
– Premature expansion in the liquid area of the coolant circuit (loss
of charge)
– Flow quantity too high (see defined maximum flow rate)
– Insufficient heat exchange in the plate heat exchanger or the
ribbed pipe heat exchanger
– 4-way valve faulty
F.582 EEV fault – Cable insulation faulty
– Connection broken
F.585
Sensor fault: Temp. building circuit EEV
2)
– Sensor is faulty or incorrectly connected to the main PCB
F.685 Communication fault: eBUS – The product is not connected to the controller
– Polarity inverted
F.750 Connection fault: Compressor – Cable insulation faulty
– Connection broken
F.751 Compressor: Overcurrent fault – The product's voltage supply is too low
– The ribbed pipe heat exchanger or heat exchanger is dirty
F.752 Fault: Inverter – Inverter box damaged
– The cooler inverter box is blocked.
– Faulty voltage supply
– The "Max. duration power supply cut-off" parameter has been
set poorly (see the "Heat pump setting parameters" section in
the appendix).
F.753 Connection fault: Inverter not recognised – The connection between the main PCB and the inverter box is
damaged or broken.
– The inverter box is not switched on.
– The "Max. duration power supply cut-off" parameter has been
set incorrectly (see the "Heat pump setting parameters" section
in the appendix).
F.754 Fault: Fan unit – The connection between the main PCB and the fan PCB is dam-
aged or broken.
– The fan PCB is faulty
F.755 Fault: 4-way valve position incorrect Mechanical or electrical problem. Move the 4-way valve away from
the controller. When moving it, check that the coil voltage is correct.
F.774 Sensor fault: Air inlet temperature – The temperature sensor is faulty or incorrectly connected to the
main PCB.
F.1288 Fault: SP1 cylinder temperature sensor Sensor is faulty or has not been correctly connected to the VWZ AI
heat pump control module.
Connection fault: Accessory modules Fault in the VWZ AI heat pump control module (the connection
between the display and the main PCB is faulty).
1) Sensor on the evaporator
2) Sensor on the condenser