BoilerFaultCodesWhat the manual says
Manufacturer manualMain 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 boiler's main control board suffers an internal electronic failure, meaning it can no longer process data or send signals to other components. The most common reasons for this are general wear and tear of the electrical circuits over time or damage caused by a power surge in the home.
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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Related fault codes
All 52 fault codes on the Flexicom hx
Seeing a different code? Every code this model can display, in one place.