Your boiler has lost its ability to regulate hot water temperature correctly because of a wiring or sensor fault, meaning you likely have no hot water.

DHW sensor short circuit – check connections to domestic hot water (DHW) sensor

What causes this fault?

This fault occurs when the boiler's internal computer receives an impossible electrical signal from the hot water temperature sensor. It typically happens because the sensor’s internal components have failed or the connecting wires have become damaged or loose, preventing the boiler from knowing how hot the water is.