BoilerFaultCodesYour boiler is having trouble sending signals between its internal electrical parts, which is preventing it from working correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: COMMUNICATION FAULT: THIS FAULT MAY BE OCCASIONAL AND CAUSED BY ELECTROMAGNETIC INTERFERENCE, OTHERWISE CHECK THE MAIN CONTROL BOARD (PCB).
What causes this fault?
This fault occurs when the 'brain' of the boiler loses contact with its internal electrical components, meaning it can no longer send or receive instructions. It is usually caused by a loose connection in the wiring or a hardware failure within the main control board itself. Occasionally, outside electrical interference from other household appliances can disrupt these signals and trigger the error.
DIY fix possible
Turn the boiler off at the fused spur switchWait 60 secondsTurn the power back on and press the 'Reset' button
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A boiler cover plan would cover faults like 20 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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