High
4 red flashes on Baxi 80e

Your boiler is unable to safely clear exhaust fumes from the system, which is preventing it from lighting to provide heat and hot water.

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.

Technical description

Fan fault

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

3 red flashesView →5 red flashesView →

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