BoilerFaultCodesYour boiler has lost communication with the internal valve that directs heated water to either your radiators or your hot water tank, meaning your system cannot function correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Without diverter valve
What causes this fault?
This fault occurs when the boiler's main computer loses its electronic connection with the motor that moves the internal water valve. The most common reason is that the motor unit has failed internally, though it can also be caused by loose wiring or a communication error on the main circuit board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 65:0 — 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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