BoilerFaultCodesYour boiler is failing to detect a flame after it tries to ignite, meaning it will not stay lit to provide heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No or insufficient ionisation flow.
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect a steady flame during the start-up sequence, forcing the system to shut down for safety. The most common reasons are a worn-out sensor probe that can no longer 'see' the flame, a faulty ignition cable, or an issue with the gas valve not delivering the correct amount of fuel.
DIY fix possible
Check if other gas appliances, like a cooker, are working to ensure gas is being supplied to the property.Ensure your gas meter has credit if you use a pre-payment meter.Try resetting the boiler by pressing the 'Reset' button on the display panel.
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 F007 — 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.