Medium
4.2 on Baxi 825 Combi

Your boiler has detected an issue with its installation setup, often caused by a communication error between the boiler and its external controls or settings.

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

Installation regulations

From this model's manual
Verified against the Baxi 825 Combi installation & service manual, page 3.
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

E119View →E110View →E133View →

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