Medium
F.64 on Viessmann Vitodens 222-F B2TF

Your boiler is struggling to keep the flame lit while it is starting up, so it is automatically turning itself off and trying again to get back to normal.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Normal operation Flame loss during stabilisation or operating phase. Burner restarts.

From this model's manual
Verified against the Viessmann Vitodens 222 F B2tf installation & service manual, page 90.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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