BoilerFaultCodesYour boiler’s internal computer has encountered a critical electronic failure and cannot safely operate the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control box errors – possible faulty control box
What causes this fault?
This fault occurs when the boiler's central control board suffers a hardware malfunction or loses its ability to communicate with the internal sensors. The most common reason is a component failure on the printed circuit board (PCB) or a loose connection within the main wiring harness. Because the brain of the boiler can no longer verify that it is operating safely, it automatically shuts down as a 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 E10 — no call-out fees, no surprises.
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Keston C36 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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