Air Conditioner Stacking? (Rock Drake Egg hatching help pls)

[500KG]

Hey All,

I've just built 25 air con units around my building to hatch a drake egg. Then I built 12 in one area and that seems to actually work (it's a big room). I have two questions:

1. If I built air con units outside, in a colder climate (not mushroom forest) would it work better?
2. Can I stack 12 air con units on top of eachother? They dont seem to clip so it should be possible, just wanted to know if it would work.