BoilerFaultCodesYour boiler is struggling to talk to your external remote control unit, meaning the two devices aren't sharing information correctly.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Appears if the appliance is connected to the optional remote control (RC05) and there is a communication problem.
What causes this fault?
This fault occurs when the main control board in your boiler loses the digital connection with your external wall thermostat or remote control unit. The most common reason is a loose or damaged physical wire connecting the two devices, or a failure in the electronic sender unit inside the remote itself. Without this data link, the boiler cannot receive the correct signals to turn on or off.
DIY fix possible
Check if the batteries in your remote control unit need replacingEnsure the remote control is within signal range of the boilerTurn the boiler power off at the fused spur, wait 30 seconds, and turn it back on to reset the connection
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 05 — no call-out fees, no surprises.
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