High Limit Thermostat (Yellow) High

Firebird High Limit Thermostat (Yellow) Fault Code

Q: What does the Firebird High Limit Thermostat (Yellow) fault code mean?

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

Q: How much does it cost to fix Firebird error code High Limit Thermostat (Yellow)?

Typical repair cost for the Firebird High Limit Thermostat (Yellow) fault is £90-180 including labour.

Also written as HIGHLIMITTHERMOSTATYELLOW — same fault.

The Firebird High Limit Thermostat (Yellow) fault code means: your boiler has automatically shut down because the water inside has become far too hot, acting as a safety precaution to prevent damage.. It appears on 1 Firebird model in our database.

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).

Typical repair cost £90-180 (including labour)

DIY fix possible

Check that all your radiator valves are open and not turned to the off position.Inspect the system pressure gauge and top up the water if it is below 1 bar.Wait for the boiler to cool down completely and firmly press the manual reset button located under the control panel cover.

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Firebird models that show the High Limit Thermostat (Yellow) fault code

Click a model for the full fault code list and model-specific repair notes.

Enviro Combi 26 Repair: £90-180

Source

Firebird High Limit Thermostat (Yellow) fault code information on this page is sourced and cross-checked against the official Firebird service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026