BoilerFaultCodesA small cooling fan inside the boiler's control panel has stopped working, which prevents the system from starting to ensure the electronics do not overheat.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal fan (inside control box) does not run
What causes this fault?
This fault occurs when a small dedicated cooling fan located inside the boiler's main control box fails to spin up. Over time, the fan motor can burn out or become clogged with dust, preventing it from cooling the sensitive electronic components. As a safety precaution, the boiler will refuse to ignite to prevent the circuit board from suffering permanent heat damage.
This fault is more common during the summer months or during periods of heavy use, as higher ambient temperatures make it harder for the control box to stay cool without a functioning fan.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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