BoilerFaultCodesYour boiler has failed to ignite, which means it cannot light the gas to provide 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: All Boilers
What causes this fault?
This fault occurs when the boiler's internal computer tries to start the combustion process but cannot detect a flame. The most common reasons are a temporary interruption in the gas supply, a blocked burner, or a build-up of carbon on the probes that spark the flame. If the sensors don't see fire within a few seconds, the boiler shuts down as a safety precaution.
This fault is frequently reported during the first cold snap of winter, as gas valves can occasionally stick after being inactive throughout the summer months.
DIY fix possible
Check if other gas appliances, like a cooker, are working to ensure gas is reaching the property.Press the 'Reset' button on the boiler control panel and wait for it to restart.In freezing weather, check that the white condensate pipe going outside isn't frozen and thaw it with warm water if necessary.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 501 — 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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