BoilerFaultCodesYour boiler is failing to light the gas burner, meaning it cannot produce any heat 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 signal
What causes this fault?
This fault occurs when the boiler attempts to start up but cannot detect a flame after several tries. The most common reasons are a lack of gas supply to the unit, a worn-out ignition spark, or a buildup of carbon on the sensor that tells the boiler it is safe to stay on.
This fault can be more frequent during extreme cold snaps if the external gas meter regulator freezes or if there is a blockage in the condensate drain pipe.
DIY fix possible
Check if other gas appliances in your home, like a hob, are working to ensure gas is reaching the propertyEnsure your gas meter has credit if you are on a prepay systemCheck if the gas isolation valve under the boiler is fully openPress the 'Reset' button on the boiler control panel once
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 4 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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