BoilerFaultCodesYour boiler has temporarily stopped working because it has detected a specific operating condition that requires it to pause for safety or system protection.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Shut-off mode
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the water temperature is rising too quickly or has exceeded safe operating limits. This is usually caused by a lack of water flow through the heat exchanger, often due to a pump failure or a blockage in the system pipework. To prevent components from warping or melting, the boiler shuts down until the temperature drops back to a safe level.
This issue often surfaces during the first cold spell of autumn when the heating is turned on after a long summer break, as internal pumps can seize during periods of inactivity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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