BoilerFaultCodesYour boiler is staying on and continuing to heat up even after it has reached the correct temperature, which can lead to overheating.
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.
What causes this fault?
This fault occurs when the internal sensors or fuel controls fail to stop the burner from firing once the water is hot enough. This is usually caused by a faulty control thermostat that cannot detect the temperature accurately or a mechanical failure in the gas valve that prevents it from closing.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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