High
E.04 – .06 on Baxi 400 Combi (range)

Your boiler has shut down because it is getting too hot inside, likely due to a blockage in the air pipes or a failure in the system that moves water around.

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

Permanent fault. Critical flue gas temperature value reached, no circulation or sensor 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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