Tuesday-Sunday worked fine.
Monday ... Decided to play with the settings. Managed to reset the PID to factory default.
Tuesday... coffee seemed cooler than normal.
Tuesday evening... researched PIDs. Discovered that they usally have an "offset" so that the displayed temperature, is correct allowing for the drop in temperature from the boiler to the coffee. As a result the temperature of my coffee was less than it should have been.
Wednesday... phoned the dealer, and after several calls from Netherlands to Italy, was informed that the offset was 20C !!
Strangely enough the cool brewed coffee still tasted reasonably good!