Emergency
E 12 on Keston C55

Your boiler has detected that it is getting dangerously hot and has shut itself down to prevent damage or fire risk.

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

Thermal fuse blown or flue overheat thermostat activated.

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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