High
F.37 on Vaillant Turbomax Plus 828

Your boiler has detected a problem with how the internal fan is spinning, which means it cannot safely vent exhaust fumes and has shut down as a 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

(837/637 only) | The rotary speed of the fan is too high or too low | Air pressure switch defect; fan defect; electronics defect

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.32View →F.33View →

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