[Nikolai]

AC_Hacker:

Here's why I'm asking: My goal is to achieve a system with maximum heat gain, so I came up with the idea to remove the second stage of heat exchange too, and to get so-called "direct-direct system".

I have no knowledge about the need for the return of oil in the compressor (in details), but I suppose that if I could achieve that the compressor is at lowest point in system.

I think it would be main problem, but if we could resolve it we could get one very efficient system.



// on second picture should be shown a water running trough underground heating, not refrigerant