BoilerFaultCodesWhat the manual says
Manufacturer manualPrinted circuit board (PCB) fault
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 main control board's internal components or solder joints fail due to age, heat stress, or minor electrical surges. Because this part acts as the boiler's brain, any breakdown in its circuitry means it can no longer safely coordinate ignition or monitor safety sensors.
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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