BoilerFaultCodesYour boiler is failing to light the gas flame properly and has locked itself out 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: The boiler will shut down after the lighting sequence fails twice.
What causes this fault?
This fault occurs when the boiler attempts to ignite the gas but fails to detect a stable flame after two consecutive tries. The most common reasons include a worn-out ignition spark that can no longer reach the burner or a gas valve that is failing to open and release fuel. In some cases, the control board may be unable to sense the flame even if it has successfully lit.
This fault can be more prevalent during the first cold snap of autumn when a boiler that has been idle all summer is suddenly forced to work at full capacity.
DIY fix possible
Check that your gas emergency control valve is in the open positionCheck if other gas appliances in your home, like a hob, are workingPress and release the reset button 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 Reset permanently ON and Burner Lit flashing fast (8 Hz) — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Glow-worm Micron 30ff 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.
Affiliate links — we may earn a commission at no extra cost to you.