BoilerFaultCodesYour boiler has shut down completely for safety reasons and will not provide heating or hot water until it is manually reset or repaired.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Safety LOCK-OUT condition
What causes this fault?
This fault occurs when the boiler's control system detects a failure in the ignition process or a safety breach, leading to an immediate shutdown. The most common reasons include the burner failing to light, a loss of flame signal during operation, or an internal component like the fan or gas valve not responding correctly. It is a protective measure designed to prevent the boiler from running in an unsafe condition.
DIY fix possible
Locate the reset button on the front control panel.Press and hold the reset button for at least two seconds.Wait to see if the green light replaces the red light and the boiler fires up.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
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