BoilerFaultCodesYour boiler is unable to light the flame needed to heat your water and radiators, often due to a temporary interruption in the gas supply.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Gas supply problem, Gas line requires purging, Reversed polarity, Broken internal flue joint. Burner has failed to ignite, or the flame supervision system has failed to detect a flame.
What causes this fault?
This fault occurs when the boiler tries to start up but cannot successfully create or see a flame at the burner. The most common reasons are a temporary interruption in your gas supply, a build-up of dirt on the ignition probes, or a component failure that prevents the gas from flowing correctly. Essentially, the safety system has stepped in because it cannot confirm that the fuel is burning safely.
This fault can be more frequent during extreme cold spells if the external gas regulator or pipework becomes affected by freezing temperatures, limiting gas flow.
DIY fix possible
Check if other gas appliances, like a cooker, are working to confirm gas is reaching the property.Ensure your gas meter has credit if you use a pre-payment meter.Press the reset button on the boiler control panel and hold for a few seconds to try and restart the ignition sequence.
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 01 — no call-out fees, no surprises.
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Vokera Syntesi 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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