Your boiler's internal computer brain is unable to talk to the front display panel, 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 communication with the printed circuit board: Communication fault between the display and the printed circuit board in the switchgear box
What causes this fault?
This fault occurs when the 'handshake' between the boiler's main control board and the front display panel is interrupted. The most common reason is a loose or damaged connection cable internally, though it often signifies that the electronics have suffered a surge or a component failure on one of the boards.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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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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