BoilerFaultCodesWhat the manual says
Manufacturer manualController ABM03B error – controller internal error
From this model's manual
Verified against the Ferroli Modena He installation & service manual.
What causes this fault?
This fault occurs when the boiler's internal computer chips suffer a hardware failure or a memory corruption, meaning the board can no longer process safety data correctly. The most common reason is electrical degradation of the circuitry over time or a sudden power surge that damages the sensitive components on the PCB.
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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