I am building a new home and have decided on the HVAC setup (based significantly on information gleaned from this forum). Either a Trane XL19i or XL16i (5 ton) and either a VS90 or VS80 in a zoned system.
It looks as though the furnace will be oversized in order to match the capacity of the AC unit. I have been advised that I will probably need a 5 ton furnace to go with the 5 ton AC unit. I have not yet decided on 80+ or 90+% but will definitely have VS.
My question has to do with the benefit of VS with an oversized furnace. How much will VS help out on the oversizing issue? How low (RPM) will the VS operate? Does this have to do with the set up by the installer?
My last question has to do with furnace efficiency. Since the furnace will be oversized would it be better to go with the 80% furnace so that it will not heat the home too quickly, thus leading to overcycling?
Thanks very much.