High
F.83 on Vaillant ecoTEC plus Regular

Your boiler has detected that there is either insufficient water circulating inside it or that its internal temperature sensors are failing to register a rise in heat when the burner starts.

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

Dry fire fault

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.22View →

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