BoilerFaultCodesYour boiler has detected a problem with how it moves air and exhaust gases, which has caused it to shut down 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: Differential Air Pressure Switch Huba, Ref. 605.99482
What causes this fault?
This fault occurs when the boiler's internal sensor fails to detect the correct airflow required to safely clear exhaust gases from the flues. The most common reasons include a blockage in the flue pipe, a buildup of debris in the small plastic tubes inside the casing, or an electrical failure within the air pressure switch itself.
This fault is more common during periods of high winds, which can create back-pressure in the flue and prevent 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 E00-730 — no call-out fees, no surprises.
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