High
F.41 on Vaillant Turbomax Plus 828

Your boiler has lost its electronic configuration and no longer knows which type of gas it should be burning to operate safely.

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) | No setting for the type of gas is stored | Set gas type in PCB (see page 30)

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.61View →F.62View →

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