BoilerFaultCodesYour boiler has tried to light but failed to stay on, meaning the system has shut down for safety until it is reset or repaired.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: If Flame Failure Light is ON. Press the Reset Button. If Flame Failure occurs persistently consult your Installer or Service Engineer.
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect a steady flame after several ignition attempts. The most common reasons include a lack of gas reaching the burner, dirty electrodes that can no longer spark correctly, or a faulty sensor that cannot 'see' the flame even if it has lit.
This fault is more common during the first cold snap of winter when components that have been idle all summer are suddenly forced to work under high demand.
DIY fix possible
Check that your gas supply is active (check other gas appliances like a hob)Press the Reset button on the front of the boiler for a few secondsEnsure your condensate pipe has not frozen if it is currently very cold outside
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 Flame Failure (Red Light) — no call-out fees, no surprises.
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Potterton Promax FSB 30HE 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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