BoilerFaultCodesYour boiler has stopped working because the fan system cannot properly clear waste gases or bring in fresh air to burn fuel safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Air flow fault
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the fan isn't moving enough air to safely vent exhaust gases outside. The most common reasons are a build-up of dirt in the fan assembly, a blockage in the flue pipe, or a failure in the electronic switch that monitors air pressure.
This issue can sometimes appear during periods of high winds, which can create back-pressure in the flue and interfere with the air pressure sensor's readings.
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 02 — no call-out fees, no surprises.
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