BoilerFaultCodesYour boiler has detected that the fan, which safely removes waste gases, is spinning at the wrong speed or has stopped working entirely.
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 main control board loses communication with the fan or detects that it isn't spinning at the required speed to safely expel exhaust fumes. The most common reasons are a build-up of dirt inside the fan housing, a loose electrical connection, or a mechanical failure of the fan motor itself.
This fault can sometimes occur during period of high winds if the air pressure prevents the fan from reaching its starting speed, or after a long summer break when moving parts may have seized.
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 E05 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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