Your boiler's main control panel is failing to process information correctly, which has caused it to shut down for safety.

Display PCB fault.

What causes this fault?

This fault occurs when the boiler's front control panel stops speaking to the internal computer that manages heating and hot water. It is usually caused by a physical failure of the circuit board behind the screen or a loose connection in the wiring that links it to the main system. Because the boiler can no longer receive instructions or display accurate information, it shuts down as a safety precaution.