High
F.00 on Vaillant ecoTEC exclusive

Your boiler has lost the connection to the temperature sensor that tracks the flow of water, causing it to stop heating as a safety precaution.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Interruption:Flowsensor | NTCplugnotpluggedinorhascomeloose,multipleplugonthePCB notpluggedincorrectly,interruptionincableharness,NTCdefective

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.01View →F.73View →

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