BoilerFaultCodesYour boiler has failed to light, which means your heating and hot water will not work until the gas flow or ignition is restored.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No ignition or gas supply failure
What causes this fault?
This fault occurs when the boiler's control system attempts to light the burner but fails to detect a flame after several attempts. The most common reasons are a lack of gas reaching the appliance, a worn ignition spark electrode that cannot create a flame, or a faulty gas valve that isn't opening correctly.
This fault is more common in winter, as freezing temperatures can block external gas regulators or cause condensate pipes to freeze, both of which prevent the boiler from lighting.
DIY fix possible
Check that your gas meter has credit and that the external gas isolation valve is turned on.Check if other gas appliances in your home, such as a hob, are working correctly.Press and hold the 'Reset' button for 2 seconds to see if the boiler restarts.
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 E01 — no call-out fees, no surprises.
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Potterton Gold Combi HE 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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