Emergency
D. (1) on Potterton Kingfisher 2

Your boiler is failing to switch off when the water reaches the correct temperature, meaning the system is running constantly and 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

Main burner fails to shut down when water reaches pre-determined temperature - Thermostat out of calibration or faulty.

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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