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 boiler's internal computer chips or electrical paths fail due to age, heat stress, or a sudden power surge. The most common reason is that the delicate components on the circuit board have worn out over time, causing the system to lose its ability to communicate with the rest of the boiler safely.
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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