BoilerFaultCodesYour heat pump's external unit is unable to talk to the control panel inside your home, meaning the system cannot receive instructions to provide heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No connection Outdoor PCB to User Interface
What causes this fault?
This fault occurs when the physical wiring link between the outdoor unit and the indoor controller is broken or interference is blocking the signal. The most common reasons are loose wiring connections at either end, damage to the communication cable, or a internal electronic failure on one of the circuit boards. Without this data link, the system cannot send commands to start the fan or compressor.
This fault can sometimes appear after heavy storms or high winds if debris or movement has disturbed the external wiring connections.
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 9.1.4 — 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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