BoilerFaultCodesYour boiler is lighting but the system is failing to detect the flame, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Go to sections 'I' & 'M'
What causes this fault?
This fault occurs when the boiler successfully lights the burner but the internal sensors fail to confirm the flame is present. The most common reason is a build-up of carbon or wear on the flame sensing electrode, which prevents the signal from reaching the control board. For safety, the boiler automatically shuts down because it 'thinks' it is leaking unburnt gas.
This fault is slightly more common in winter as increased humidity or minor leaks from the heat exchanger can cause moisture buildup on the electrodes, interfering with the electrical signal.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like neon flashing (Burner extinguishes after 10 seconds) — no call-out fees, no surprises.
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Potterton Performa 30 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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