High
Red neon on Grant Vortex Pro Combi

Your boiler has automatically shut down because it detected that it is running too hot to operate safely.

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

Safety overheat thermostat has operated and automatically switched off the boiler in the case of a control malfunction causing overheating.

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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