BoilerFaultCodesYour boiler has detected an electrical communication problem with its internal control system which is preventing it from firing up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: DC supply pipe
What causes this fault?
This fault occurs when the boiler's internal computer loses the ability to communicate with the sensors that monitor the gas and water flow. It is usually caused by a physical break in the internal wiring or a failure in the electronic components on the main control board. Because the boiler can no longer verify that it is safe to operate, it shuts down immediately as a safety precaution.
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 A5 — no call-out fees, no surprises.
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