OK, you have been quoted a high end communicating 80% eff two stage furnace with a low end AC condenser. Why?

Several questions raised here.

80% eff furnace why?

A communicating furnace with a low end non communicating AC condenser.

I personally would look at a higher eff furnace, two stage var speed with at least Classic series condenser. And if staying with 80% eff furnace, then consider pairing with a HP condenser for a nice DF system.

Just hate 80% eff furnaces.

IMO

Hi TigerDunes, the contractor made it sound like 95eff furnace didn't belong in attic b/c of the condensation created. He didn't elaborate on whether it was against code or just a pain in the wallet to retrofit to accomdate the new needs, but he didn't even pose it as a solution. We actually have 2 systems, and he did say we could do the 95eff in the crawl space. I really wanted the two systems to be the same, so we proceeded down the 80eff route.

At this point my biggest concern is the longevity of the compressor without some of the features the classic/prestige offer, such as high/low pressure switches and the prestige offers hard start assist. They have the same warranty, but I expect the components to last longer than warranted, and if spending some cash up front will buy me more life out of the compressor, I'm OK with that.

I'm also not sure about the Pro8000 stat. Seems like with variable speed furnace I'd want a stat that utilizes that feature to control humidity?

Your original post did not state this was attic installation. With that being the case, I would stick with the 80% eff furnace for the upstairs system. It will require a true two stage thermostat for best operation that I hope your dealer has included. Also, I would want a whole house air filter media cabinet. I will stick with initial recommendation to upgrade the AC condenser and possibility of HP if electric rate is favorable.

IMO
Good Luck