Emergency
H7 on Worcester Bosch Highflow 250

Your boiler has detected that it is getting too hot and has automatically shut down to prevent damage or dangerous overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Terminals L - N not supported / Safety overheat thermostat fault

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E9View →

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