I think the rheem quote looks good. If its 8-grand less thats a major reason to go with that quote. 95% efficient 2 stage furnaces are plenty comfortable and efficient. A good thermostat will make it run in the low-stage most of the time. True modulating or 3 stage furnaces are more comfy but maybe its overkill. Just make sure your not oversized. Remember 95% efficient furnaces put out 15% more heat than the same size 80% efficient furnace. FYI - those rheem A/C's in the quote are plenty efficient also and RHEEM makes good quality stuff I think.

Yes Natural Gas Furnace for Heating along with the AC condenser. I have read up a lot on zoning, it seems to me like there are not a lot of installers in the industry that really know how to set them up properly. There also is a lot of negative information on zoning as it relates to the troubles a by-pass can cause to your systems efficiency. That is why I was leaning towards the two unit system, however need to figure out the proper size for each level. I know the best thing to run is a Manual J on the place however as a starting point what is the general rule based on square footage in determining the tonnage and BTU for a heating and cooling system? That along with how does the rising of hot air and the dropping of cool air determine the size you would go with? Any help would be appreciated.

The biggest problem with HVAC zone systems is knowing when to choose it as a solution and when not to. Some HVAC companies it's about "sell, sell, sell" whether or not it works... there's more money in "sell, sell, sell" --- when it's only about money? So does the comment above mean I do it for free? No. If you think that you are reading things that aren't there. New construction? best to choose separate systems 9 times out of 10. In order for a zone system to work, you have to know what you are doing. Most HVAC companies staff (the techs they send you) are 20-30 year olds. How much practical experience could they possible have? It's best for HVAC zone systems to be an elegant solution. A HVAC zone system is a tool in the tool bag. Not all homes are suitable for zone systems. Some homes there is no other way, and in some cases complications to those problems will make an HVAC zone system design possibly more prone to problems. You have a problem now, do you want more problems. These decisions among others are decided "in person" --- so considering that becareful what information you decide upon from the internet. Just because it's here doesn't necessarily mean it's true. That said: Depending on equipment level chosen, how many different floors you have in your structure, how much room you have available... will all be factors that make you decide one way or another. From there it's in your best interest to pick a contractor that is skilled: especially when it comes to HVAC zone systems. (there's a lot of garbage out there.) (click to enlarge if necessary) I service the Katy, Texas area.

I completely agree with Fudd (and would have used a stronger word than "baloney.") Any company that won't do a "Manual J" load calculation on your home should NOT be hired to install your new system! Here is a good explanation of why doing a load calculation is so important: https://www.pvhvac.com/blog/why-the-manual-j-load-calculation-is-key-to-hvac-design And a 96% efficient furnace is definitely preferable to the 80% offering (in which 20% of the gas you purchase to make it run -- is wasted.) In this day and age, please go with the furnace that only wastes 4% of the gas you purchase. Even your gas utility bill with thank you, with lower monthly costs to run your new furnace (than if you'd bought the 80% efficient version).