High
381 on Viessmann Vitodens 100-W B1GA

Your boiler has stopped because the flame inside went out while it was trying to heat your water or home.

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.

What the manual says

Manufacturer manual

Burner in a fault state Flame loss during operating phase

From this model's manual
Verified against the Viessmann Vitodens 100 W B1ga installation & service manual, page 61.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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