BoilerFaultCodesYour boiler is failing to turn off even when the water has become hot enough, which could lead to dangerous 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 predetermined temperature
What causes this fault?
This fault occurs when the boiler's internal sensors or control valve fail to cut off the gas supply once the water reaches its target temperature. The most common reason is a faulty control thermostat that can no longer detect heat correctly, or a gas valve that has become physically stuck in the open position. Because the burner continues to fire indefinitely, the system is at risk of dangerous overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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