BoilerFaultCodesYour boiler has failed to ignite and is not producing heat, which is usually due to an interrupted gas supply or a problem with the internal spark system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Lack of gas, a fault with the ignition or flue – may need to adjust the gas valve or replace a defective electrode lead.
What causes this fault?
This fault occurs when the boiler tries to light the flame but fails to detect one, causing the system to shut down for safety. The most common reasons are a temporary interruption in the gas supply, a build-up of carbon on the ignition probes, or a component failure that prevents the spark from starting the combustion process.
This issue can occur more frequently during extreme cold snaps if the external gas meter regulator freezes or if the gas supply pressure drops due to high local demand.
DIY fix possible
Check if other gas appliances, like a cooker, are working to confirm gas is reaching the propertyEnsure your gas meter has credit if you use a pre-payment accountPress the reset button (indicated by a flame with a line through it) and hold for two 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 F.1 — no call-out fees, no surprises.
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Vaillant EcoMax Pro 18/28E 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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