BoilerFaultCodesYour boiler has failed to ignite several times or has potentially gotten too hot, causing it 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: The boiler fails to light up to five times during the ignition sequence, the boiler will go to lockout. (This can also indicate an overheat condition if the fan or pump continues to run for up to 10 minutes).
What causes this fault?
This fault occurs when the boiler tries to light the flame several times but fails, often due to a lack of gas or a weak spark at the burner. It can also be triggered if the unit detects it is becoming too hot, forcing a shutdown to prevent damage to internal components. The most common reasons include a worn-out ignition lead, a fault with the gas valve, or a sensor that is incorrectly reading the temperature.
This fault often appears during the first cold snap of autumn when boilers are suddenly required to work harder after being idle throughout the summer.
DIY fix possible
Check that your gas pre-payment meter (if applicable) has credit.Ensure the gas supply valve is open.Press the 'Mode' or 'Reset' knob to the reset position to attempt a restart.
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 red operational light 2 (E) illuminated — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Ideal Icos HE 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.