High
Safety Thermostat neon on Baxi Promax Heat

Your boiler has switched itself off because it got too hot, likely due to a circulation problem or a temporary blockage in the system.

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

The boiler has shut down in the event of the system or the boiler overheating.

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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