I have read that the vision pro 8321 is a 3 stage t-stat
however there seems to be the opinion that it can't be used on 1 stage
heat pump w/2 stage fossil back-up.
I like the technology of the VP does anyone make a similar
device that can be used in the setup I have.
Also I read the manual for Vision pro and
under the instructions for testing it it says under under installer test #3 option 2 both the stage 1 and 2 turn on. Can doing this damage the heat pump? I didn't think you should run
the gas heat with the heat pump running.