BoilerFaultCodesYour boiler's internal computer parts are having trouble talking to each other, which means the system has stopped working for 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 error
What causes this fault?
This fault occurs when the boiler's internal control board loses touch with the display panel or the smart sensors inside the unit. It is usually caused by a loose connection in the wiring or a tiny electrical component failing due to age and heat. Because the brain of the boiler can no longer see what the rest of the components are doing, it shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like E83 — no call-out fees, no surprises.
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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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