High
F2 on Viessmann Vitodens 100-W

Your boiler has switched itself off because it has detected that it is running too hot and needs a professional to check it is venting heat correctly.

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

Burner in fault state, temperature limiter has responded

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

F4View →F5View →

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