High
Vitodens 100-W on Viessmann Vitorond 100

Your boiler has stopped working because the burner is unable to light or stay lit, meaning your heating and hot water will be unavailable.

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 blocked

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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