High
SAFETY HIGH LIMIT THERMOSTAT on Firebird Enviro System

Your boiler has switched itself off because it got too hot, acting as a safety measure to prevent damage.

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

Fixed at 110˚C, this system protects the boiler in the event of the control thermostat failing. It will shut the boiler off and require the limit button to be pushed to restart.

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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