High
布 & 皿 neons flashing on Baxi Combi Elite

Your boiler has reached an unsafe temperature or detected excessive heat in the exhaust, causing it to shut down for safety.

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

Overheat thermostat or Flue thermostat activated

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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