BoilerFaultCodesYour boiler has switched itself off because the fan, which safely removes exhaust fumes, is not spinning at the correct speed.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fan speed incorrect
What causes this fault?
This fault occurs when the boiler's control system detects that the fan is not rotating at the speed required to safely clear combustion gases from the flue. The most common reasons are a build-up of debris within the fan motor, a blockage in the air pressure tubes, or electrical wear and tear on the internal circuit board which prevents it from controlling the fan properly.
This fault is slightly more common in autumn and winter, as heavy winds can create back-pressure in the flue, or spiders may crawl into the pressure sensing tubes during colder months.
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 E05 — no call-out fees, no surprises.
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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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