High
Overheat thermostat on Grant Euroflame

Your boiler has automatically turned itself off because it detected that it is running hotter than it should be.

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 should switch off on the overheat thermostat. Replace the phial. Unscrew and remove the reset button cover, press the reset button and replace the cover.

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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