BoilerFaultCodesYour boiler's internal control screen is unable to talk to the main computer, which prevents the heating from turning on.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: User interface not compatible with boiler
What causes this fault?
This fault occurs when the main control board and the display screen fail to recognize each other's communication signals. It is usually caused by a software mismatch after a repair or a physical hardware failure where a component's internal memory has become corrupted. Without this digital handshake, the boiler stays off because the two parts cannot agree on how to safely run the system.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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