BoilerFaultCodesYour boiler has failed to light or has tripped its safety cut-out because it got too hot.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ignition failure or overheat condition. Check gas pressure, reset button, and overheat thermostats.
What causes this fault?
This fault happens when your boiler tried to light three times but couldn't detect a flame, or if the system grew too hot and triggered a safety shutdown. The build-up of debris on the spark probes or a blockage in the internal pipework are the most frequent reasons your boiler stops working in this state. It is essentially a protective measure to prevent the appliance from operating under unsafe conditions.
This fault is more common during the first cold snap of autumn when a boiler that has been idle all summer is suddenly forced to run at maximum output.
DIY fix possible
Check if your gas supply is active (e.g. check other gas appliances or prepaid meter credit)Press and hold the 'Reset' button for five secondsEnsure all radiator valves are open and the system pressure is between 1 and 1.5 bar
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 LED 1 and LED 3 on, plus LED 4 on — no call-out fees, no surprises.
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