BoilerFaultCodesWhat the manual says
Manufacturer manualPrinted circuit board (PCB) error
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This fault occurs when the electrical components on the main control board suffer a critical failure, preventing the system from processing instructions correctly. The most common reason is general wear and tear over many years of use, though it can also be triggered by a sudden power surge or moisture getting into the casing.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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