BoilerFaultCodesYour boiler is failing to light the gas burner, meaning it cannot create the heat needed for your heating or 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: No flame detection
What causes this fault?
This fault occurs when the boiler tries to light the gas three times but fails to sense a flame. The most common reasons are a temporary interruption in your gas supply, a build-up of carbon on the spark electrodes, or a component failure that prevents the gas valve from opening correctly.
This issue can be more frequent during extreme cold spells if the external gas regulator freezes or if the gas pressure drops due to high local demand.
DIY fix possible
Check that your gas prepayment meter has credit (if applicable).Ensure other gas appliances in your home, like a cooker, are working correctly to confirm gas supply.Restart the boiler by turning the power off and on or pressing the reset button.
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 2 — no call-out fees, no surprises.
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Ideal Systemiser SE is discontinued — time for a new one?
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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