Medium
F.80 on Vaillant ecoTEC exclusive

Your boiler is having trouble communicating with the temperature sensor in your hot water storage unit, meaning your water might not heat up correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Fault:actoSTORinletsensor OnlyinconjunctionwithF.91 NTCdefective,NTCcabledefective,defectiveplugconnectiononNTC, defectiveplugconnectionontheactoSTORelectronics Sensorplughasshorttoearthtothehousing,shortcircuitincablehar- ness,sensordefective

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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