High
3 red flashes on Baxi EcoBlue Advance Heat

Your boiler has tried to light itself several times but cannot establish a flame, meaning you will have no heating or hot water until it is reset or repaired.

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

Ignition fault. Boiler has attempted to light 5 times and failed.

From this model's manual
This code was read directly from the manufacturer service manual for this model.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler cannot successfully create or detect a flame after several attempts. The most common reasons include a lack of gas reaching the unit, a worn-out ignition spark, or a sensor that can no longer confirm the flame is safely lit.

This fault is more common in winter, as frozen condensate pipes can back up and prevent the boiler from igniting properly.

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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