BoilerFaultCodesYour boiler is having trouble managing the flow of air and exhaust gases needed for it to run safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Ventilation
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that air isn't moving through the system correctly to support safe combustion. The most common cause is a failing fan or a blockage in the flue pipe that prevents the boiler from clearing exhaust gases effectively.
This fault can be more frequent during periods of high winds, which can cause pressure fluctuations in the flue that interfere with the air pressure sensor.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 3 — 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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