BoilerFaultCodesYour boiler's computer components are having trouble communicating with each other because they are running incompatible software versions.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Software incompatibility.
What causes this fault?
This fault occurs when the main control board and the display panel are unable to talk to each other correctly because their internal programs do not match. This usually happens after a repair where a new part has been installed that is running a different software version than the original components. It essentially means the boiler’s 'brain' and its 'voice' are no longer speaking the same language.
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 F20 — no call-out fees, no surprises.
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