BoilerFaultCodesTechnical 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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