Item Previous State/Value

Setup, Configuration and Use Scripts & Rules
4

Temperature as Number solved in that way:

var TempBefore = (previousState as QuantityType).doubleValue
var TempBecome = (Boiler_Sensor_SensorTemperature1.state as QuantityType).doubleValue

logInfo(“test”,"changed from " + TempBefore + " to " + TempBecome)

Now getting in log just numbers as wanted to, as well as possible to compare etc.