BoilerFaultCodesYour boiler has detected an internal electrical connection issue that is preventing it from running safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Interruption in cable harness: Cable harness faulty
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with its safety sensors due to a break in the electrical circuit. It is typically caused by a loose connection, a damaged plug on the wiring loom, or a failure within the main control board itself.
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 F.25 — 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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