High
Indicator Neons on Main Combi 24

Your boiler is displaying warning lights to signal an internal fault that is preventing it from operating correctly.

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

Used to monitor the boiler operation and identify potential fault conditions as part of the Fault Finding section (detailed in Section 13.0).

From this model's manual
Verified against the Baxi Boiler Maxflow Combi Wm installation & service manual.
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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Related fault codes

E01View →E02View →E03View →

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