BoilerFaultCodesYour boiler's internal computer has encountered a software or hardware communication error and has stopped working to protect itself.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler's internal computer chips fail to talk to each other correctly, leading to a total communication breakdown between the main brain and the control panel. The most common reason is a physical hardware failure on the main circuit board or a corruption in the software that manages the boiler's safety checks.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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