BoilerFaultCodesYour boiler has tried to light several times but cannot establish a flame, causing the system 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: Ignition lockout
What causes this fault?
This fault occurs when the boiler attempts to ignite several times but fails to detect a sustained flame. The root cause is often a lack of gas reaching the burner or a component like the spark electrode being unable to create the initial fire. It can also happen if the sensor that monitors the flame is dirty or damaged, meaning the boiler shuts down because it cannot 'see' that it is actually lit.
This fault is more frequent during extreme cold snaps, as external gas meters or pipes can occasionally suffer from pressure drops or freezing issues.
DIY fix possible
Check that your gas emergency control valve is in the 'on' positionIf you have a pre-payment meter, ensure you have sufficient creditPress the reset button on the boiler control panel for 3 to 5 seconds
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 E01 — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
Affiliate links — we may earn a commission at no extra cost to you.