BoilerFaultCodesYour boiler has detected an issue with how exhaust gases are being cleared from the system, and it has shut down as a safety precaution.
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 harmful exhaust gases are not being shifted out of the flue correctly. It is usually caused by a blockage in the air pipes, a failing fan that cannot create enough suction, or a perished rubber tube inside the unit. The boiler shuts down immediately to ensure These fumes do not spill back into your living space.
This issue can be more common during periods of high winds, as strong gusts can sometimes interfere with the pressure balance required for the switch to stay closed.
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 E03 — no call-out fees, no surprises.
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