BoilerFaultCodesYour boiler has shut itself down for safety reasons and needs to be manually restarted to resume heating and hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Safety lockout. To reset the boiler, turn the left knob on position (reset) position, wait one minute to cool down the boiler, and then turn it on previous operating position.
What causes this fault?
This fault occurs when the boiler's internal sensors detect an unsafe operating condition, such as the water getting too hot or the burner failing to light correctly. As a protective measure, the system 'locks out' to prevent any damage to the internal components or your property. The most common reasons include a buildup of air in the system, a blockage in the pipework, or a failure in the ignition process.
DIY fix possible
Turn the left-hand control knob to the 'Reset' positionWait for approximately one minute to allow the system to cool downTurn the knob back to your desired temperature setting
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