BoilerFaultCodesTechnical 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 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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