BoilerFaultCodesYour boiler is failing to light the burner and has shut itself down for safety after three unsuccessful attempts.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The Status/Function display will show an A and the Flow Temperature & settings display will show 01, 02 or 03. After 3 ignition attempts the control will go to lockout.
What causes this fault?
This fault occurs when the boiler tries to light the gas but the internal sensors cannot detect a flame or a spark. The most common reasons are a worn-out ignition spark probe, a faulty gas valve not releasing fuel, or the main control board failing to send the correct signals. It can also be caused by a lack of gas supply to the property following a meter problem.
DIY fix possible
Check if other gas appliances, like a hob, are working to ensure gas supply to the propertyCheck if your gas meter has credit (if using a pre-payment meter)Press the 'Reset' button on the control panel to clear the lockout
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 A — no call-out fees, no surprises.
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Potterton Envoy 30 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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