BoilerFaultCodesYour boiler communication module has a permanent fault that is preventing the system from talking to its controls correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Constantly ON
What causes this fault?
This fault occurs when the boiler's internal communication hardware suffers a permanent electronic failure, meaning it can no longer send or receive data from the control system. The most common reason is a short circuit or component degradation within the LON module or the main control board itself, which prevents the boiler from identifying its operating instructions. Because the system can no longer 'talk' to its sensors and switches, it shuts down for safety.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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