BoilerFaultCodesYour boiler’s internal computer has encountered a memory error and cannot safely operate the heater.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: GFA-Asic-error
What causes this fault?
This fault occurs when the boiler's main control board experiences an internal memory failure, meaning it can no longer communicate with the safety software. It is typically caused by a microchip hardware failure or an electrical surge that has corrupted the internal data. Because the computer can no longer guarantee the boiler is running safely, it shuts down the entire system as a precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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