Where is the moisture going?
Principle: Moisture in warm arm condenses on and sticks onto cold things … like breathing on a bit of cold glass.
cold air from outside the machine gets sucked into the tumble dryer and heated up as it goes into the barrel, the moisture from the clothes evaporates into that air due to the heat … the warm, moist air then gets passed through what is a bit like a radiator which has lots of little tubes and surface area. The outside of this radiator is normally exposed to the outside air ( in fact, the cold air from outside normally gets sucked across the outside of the radiator )
The cold air passing the radiator keeps it cool. The moisture in the warm air inside the radiator condenses on the cold radiator surface and builds up till it drips down and is collected the tray ( that you haven’t emptied )
Hey presto … moisture is evaporated out of the clothes and collected in the machine.
Clever eh?