BoilerFaultCodesYour boiler is failing to detect a steady flame, which means it cannot stay on safely 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 is unable to sense a flame after trying to ignite, causing it to shut down for safety. The most common reason is a worn-out sensing probe that can no longer detect heat, though it can also be caused by a blockage in the drainage system or an incorrect mix of gas and air.
This fault is more frequent during extreme cold spells, as the internal drain pipe can freeze and back up, preventing the boiler from maintaining a flame.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F007 — no call-out fees, no surprises.
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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.
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