BoilerFaultCodesYour boiler's internal control screen is unable to communicate properly with the main computer board, often after a recent repair or parts change.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: User interface not compatible with boiler
What causes this fault?
This fault occurs when the boiler's internal display panel and the main control board are unable to understand each other's signals. It most commonly happens after a recent repair where a new part has been installed that isn't programmed correctly or is mismatched for your specific model. Essentially, the boiler’s 'brain' and 'face' are no longer speaking the same language.
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.
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A boiler cover plan would cover faults like 20 — no call-out fees, no surprises.
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