BoilerFaultCodesYour boiler's internal computer has lost contact with its sensors or other parts, meaning it cannot receive the signals it needs to operate safely.
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.
What causes this fault?
This fault occurs when the boiler's main control board loses its ability to 'talk' to the internal sensors or the display screen. The most common reason is a loose connection or a degraded wire within the internal harness, though it can also be caused by the electronic control board failing entirely. Because the boiler can no longer monitor its own safety sensors, it shuts down immediately to prevent damage.
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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