10
Status / Error message
Possible cause
Correction
A21
Excess current inverter
Excess current caused by undervoltage. Insufficient power supply. Cause is probably excessively long cable, overloading or an insuffi- ciently high power generator output.
Improve power supply or activate ECO mode.
A22
Excess temperature inverter
Ambient temperature too high or insufficient cooling.
Check whether the air vents in the electrical box are blocked. Remove dust deposits from the heat sink. The max. ambient temper- ature must not exceed 60 °C.
A23
Excess temperature com- pressor 1
Incorrect temperature measurement.
Please contact your authorised Webasto Marine dealer.
Compressor switches off in cooling mode, maximum compressor temperature reached. Sea water cooling insufficient. Sea water strainer soiled or no flow. Sea water pump defective. Refrigerant cir- cuit blocked.
Remove blockage at sea water inlet. The minimum flow rates must be complied with. Clean sea water strainer and bleed sea water cir- cuit. Operate unit for 5 minutes in heating mode (if possible) then switch to cooling mode and check whether the fault occurs again. Please contact your authorised Webasto Marine dealer.
A24
High pressure sensor
Pressure sensor defective or power circuit interruption/short circuit.
Please contact your authorised Webasto Marine dealer.
A25
Low pressure sensor
Pressure sensor defective or power circuit interruption/short circuit.
A26
Compressor temperature sensor
Compressor temperature sensor defective or break/short-circuit in electrical circuit.
A27
Data communication in- verter
No data communication between inverter and pc-board.
A28
Characteristic diagram
Compressor operation outside characteristic map. Incorrect pressure sensor measurement.
Compressor operates outside the characteristic diagram in cooling mode, maximum pressure reached. Insufficient sea water cooling. Sea water strainer soiled or no flow. Sea water pump defective; refrigerant circuit blocked.
Remove blockage at sea water inlet. The minimum flow rates must be complied with. Clean sea water strainer and bleed sea water cir- cuit. Operate the unit for 5 minutes in heating mode (if possible) then switch to cooling mode and check whether the fault occurs again. Please contact your authorised Webasto Marine dealer.
Compressor operates outside the characteristic diagram in heating mode, maximum pressure reached. Cold water pump defective. Plate heat exchanger or cold water circuit blocked. Refrigerant circuit blocked.
Check cold water flow rate and increase if necessary. Difference between evaporator inlet/outlet temperature approx. 5 K. Operate chiller unit for 5 minutes in cooling mode (if possible) then switch to heating mode and check whether the fault occurs again. Please con- tact your authorised Webasto Marine dealer.
A30
Excess temperature inverter
The permissible temperature in the inverter housing is exceeded.
Check whether the air vents in the electrical box are blocked. Remove dust deposits from the heat sink. If possible, reduce the max. ambient temperature to below 60 °C.