Lol i mostly learned from trial and error. I always set up my t-stat probe on the cool side when i was running RHPs. Easier to just raise or drop the cool side a few degrees to get the hot side where you like it. At least for me. But then again, once i got all my snakes in the basement which is half underground and more constant temps and warmer , i just quit RHPs all together and went to flexwatt for everyone. So much easier that way for me plus i dont have a bunch of wires inside the cage.