High
High limit thermostat on Firebird Envirogreen

Your boiler has detected that it has become dangerously hot and has automatically shut itself down to prevent damage, requiring a manual reset.

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.

What the manual says

Manufacturer manual

High limit thermostat indicator light. Safety system fixed at 114˚C that shuts the boiler off in the event of the control thermostat failing; requires the limit button to be pushed to restart.

From this model's manual
Verified against the Firebird Envirogreen installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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