Hi all,
I've been set a task of preparing a powerpoint presentation and reading it out in front of the class at college. This is the task;
"Describe system layout and operating principles for multi evaporator systems with independant control for each evaporator"

I've decided to explain about a VRF, however i have a few questions.

Firstly, how does heat recovery work? I know that it uses the heat from one room and transfers it to another room but this can be done with out the compressor running, or so i have heard. Is this true? and if so how?

What type of VRV/VRF's are there, i.e 2pipe (that heat or cool) 3 pipe (that can heat and cool simultaneously) and supposedly Mitsubishi have brought out a 2pipe that can do what daikins 3 pipe does, how true is this and again how does this work.

Lastly do the indoor units on VRV/VRFs have evaporator pressure regulators on or are these not needed?

Lots of questions, sorry