BoilerFaultCodesYour boiler has failed to ignite, which means it cannot light the gas flame required to provide 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: Boiler goes to lock out | Cause: No gas, Insufficient gas, Incorrect gas valve adjustment, Electrode defective, Ignition lead defect, Electronic igniter defective, Check air inlet duct
What causes this fault?
This fault occurs when the boiler attempts to start up but fails to detect a flame after several attempts. The most common reasons are a lack of gas reaching the unit, worn-out spark electrodes that can no longer create a flame, or a fault within the internal gas valve that prevents fuel from entering the burner.
This fault is more common during the first cold snap of winter, as internal components like the gas valve can seize after prolonged periods of inactivity during the summer.
DIY fix possible
Check if other gas appliances in your home, such as a hob, are working to ensure gas is reaching the property.If you have a pre-payment meter, check that you have remaining credit.Ensure your gas stopcock is fully open.Press the reset button (indicated by a flame with a line through it) for one second.
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 F.28 — no call-out fees, no surprises.
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Vaillant Ecomax 613 2 E 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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