BoilerFaultCodesTechnical 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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