BoilerFaultCodesYour boiler has detected an issue with how it clears exhaust fumes, causing it to stop running for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flue pressure switch failure
What causes this fault?
This fault occurs when the boiler's safety sensors detect that exhaust fumes are not being cleared safely through the outdoor flue pipe. It is typically caused by a blockage in the air pressure tubes, a build-up of debris in the fan, or a mechanical failure in the switch that monitors airflow.
This issue is more frequent during periods of high winds or extreme cold, which can cause pressure fluctuations or ice blockages in the external flue terminal.
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 E1 — no call-out fees, no surprises.
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