BoilerFaultCodesTechnical description
Main board fault
What causes this fault?
This fault occurs when the boiler's central control unit suffers an internal electrical failure or memory error. It is typically caused by ageing capacitors on the circuit board or sudden electrical surges that damage the delicate microprocessors. Because the 'brain' of the boiler can no longer communicate with the sensors and gas valve, the unit shuts down to prevent unsafe operation.
This fault is slightly more common during winter months when the boiler is working under high demand or following heavy thunderstorms which can cause electrical spikes in the local grid.
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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