Your boiler has detected an electrical fault with the internal fan, which is preventing the unit from starting up 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: Fan Connections Short Circuit
What causes this fault?
This fault occurs when the boiler's control board detects an electrical short circuit within the fan system. It is usually caused by water ingress onto the electrical components, a degraded internal wiring harness, or a failure in the fan motor's windings. For safety, the boiler will prevent the ignition sequence until the electrical circuit is restored to a safe state.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like J61 — 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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