BoilerFaultCodesYour boiler has tried to light itself five times and failed, so it has shut down for safety purposes.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: IGNITION LOCKOUT: The appliance will enter a lockout condition in the event of the burner failing to ignite (after 5 attempts).
What causes this fault?
This fault occurs when the boiler's internal computer tries to light the gas burner but cannot confirm a flame is present. The most common reasons include a lack of gas supply to the unit, a blocked burner, or the ignition components being worn out and failing to create a spark. It can also happen if the sensor that detects the flame has become dirty or damaged.
This fault is more common in winter, as extremely cold temperatures can cause external gas meters to freeze or moisture in the gas line to restrict flow.
DIY fix possible
Check if your gas supply is active (e.g., check other gas appliances like a hob)If you have a prepaid gas meter, ensure it has sufficient creditPress and hold the reset button for five seconds 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 Central heating demand indicator flashes slowly (approximately once per second) — no call-out fees, no surprises.
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