BoilerFaultCodesYour boiler is unable to start up safely because it cannot confirm that the fan is moving air through the system correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner does not start. Air pressure switch does not close.
What causes this fault?
This fault occurs when the boiler's internal safety checks fail to detect the necessary airflow required to start the combustion process. The most common reason is that the fan is either not spinning fast enough or a small rubber tube inside the unit has become blocked or perished, preventing the sensor from 'proving' it is safe to light the burner.
This fault can be more common during periods of high winds, as strong gusts can occasionally create back-pressure in the flue that prevents the air pressure switch from closing correctly.
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 E06 — no call-out fees, no surprises.
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Viessmann Vitodens 100 Compact is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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