BoilerFaultCodesYour boiler's internal electronic components are having trouble communicating with each other because the control boards are not compatible or correctly configured.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Interface board compatibility fault
What causes this fault?
This fault occurs when the boiler's internal computer chips cannot speak the same language, usually after a repair where a new part has been installed. The most common reason is that the main control board and the display screen board are mismatched versions or have not been digitally 'paired' correctly. In some cases, a sudden power surge can scramble these settings, causing the components to stop recognizing each other.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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