BoilerFaultCodesYour boiler has failed to light properly and has safety-locked itself to prevent gas buildup.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Lockout condition (check pilot, gas valve, or ignition)
What causes this fault?
This fault occurs when the boiler's safety system fails to detect a flame after the gas has been turned on. The most common reason is a blocked pilot light injector or a faulty sensor that cannot confirm the burner is safely lit. Because the boiler is unsure if the gas is burning, it shuts down completely to prevent unburnt gas from building up inside the unit.
This issue is more common in autumn when homeowners first turn their heating back on, as dust can settle in the pilot assembly during the summer months.
DIY fix possible
Check that your gas pre-payment meter (if applicable) has creditEnsure other gas appliances in your home, like a hob, are working correctlyGently press the reset button or turn the control knob to 'Off' and back to 'On' after 30 seconds
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like LED SHOWING RED LIGHT AFTER APPX 20 SEC — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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