High
High Limit Thermostat (Yellow) on Firebird Enviro Combi 26

Your boiler has automatically shut down because the water inside has become far too hot, acting as a safety precaution 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

This yellow light indicates that the high limit thermostat has been activated. This is a warning sign that the water temperature in the boiler has reached an ecessively high limit (110°C).

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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