Medium
I.57 on Viessmann Vitodens 222-F B2TF

Your boiler has been temporarily switched off by an external device, such as a smart home controller, an underfloor heating safety switch, or a frost protection unit.

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

External blocking active

From this model's manual
Verified against the Viessmann Vitodens 222 F B2tf installation & service manual, page 111.
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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Related fault codes

I.58View →I.59View →

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