BoilerFaultCodesYour boiler has detected an issue with the fan that clears exhaust gases, preventing the system from starting for safety reasons.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Problem with fan – possibly no signal
What causes this fault?
This fault occurs when the boiler's main computer cannot confirm that the fan is spinning at the correct speed to safely expel exhaust fumes. The most common reasons are a physical failure of the fan motor, a loose connection in the wiring, or a fault on the control board that prevents power from reaching the fan.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E05 — no call-out fees, no surprises.
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