BoilerFaultCodesYour boiler's internal components are having trouble talking to each other, which has caused the system to stop working for your safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Communication
What causes this fault?
This fault occurs when the boiler's main control board loses its connection with the display panel or internal sensors, similar to a computer losing its connection to a keyboard. The most common reason is a loose electrical connection or a component failure on the circuit board that prevents these parts from sharing vital safety information.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 5 — no call-out fees, no surprises.
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