BoilerFaultCodesYour boiler's main internal computer has developed a fault and can no longer communicate with the rest of 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: Internal control board fault
What causes this fault?
This fault occurs when the boiler's internal computer chips or electrical circuits suffer a hardware failure, often due to age or heat stress over time. The most common reason is that a component on the control board has burnt out or lost its ability to process data, meaning the boiler can no longer safely manage the ignition or heating process.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E10 — no call-out fees, no surprises.
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Potterton Envoy 30 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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