Question about old air conditioning

Hello!

At 4°C outside temperature this morning, I had to heat. I noticed that after a short drive warm air came from the ejectors, which is so normal. It eventually became lukewarm. Colder.

With the newer climate that I had once installed in the A4, it was different, since the warm air was actually kept constant.

Or is it the case with the old climate that when the desired temperature is reached, e.g.22 °C, the heating only blows more lukewarmly and then becomes more whimsical when the internal temperature drops?

Thank you for your help! Sorry, I've never really ridden with my thickness at low temperatures.

Lg, Daniel