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.

Yeah, I thought about some kind of pressure test, but from what I could tell, it would have taken some extensive repair work just to put the system back to a loop of some kind worthy of being tested. So, it's too late now anyway. The Base Board is gone. It really was a mess, and if I ever want to, I could always add some clean new radiators or base boards to the rooms that need it. That being said, I have a decision to make: Option #1 - Variable Speed Air Handler Model#FE4ANF003Twith a 3-Ton, 16 SEER 2 Stage Heat Pump with Air Conditioneing Unit Model#286BNA036. Option #2 - Variable Speed Air Handler Model#FE4ANF005Twith a 3-Ton,20 SEER Inverter Heat Pump with Air Conditioneing Unit Model#280ANV036 Both Systems Equiped with Evolution Zone Controls for 2-Zone Heating and Cooling System. 15 KW Heat Strip ect. Option to add Humidifier and Media Filter +$1,000. The installer did an operating cost analysis and it showed the Extreme System (20 SEER) being just a bit better in cooling, but $900/year less in heating. Which to I pick?

Solution to this problem. When you update your system from single stage to 2 stage, you must have C wire from outside unit. My old single stage system came with 3 wires from outside unit to indoor (blower) and Indoor unit to thermostat had 5 wires. I solve this problem with new wiring the whole house. I install 4 wires from outside unit to indoor (blower) (red(Rh), blue(C), yellow(Y1), purple (Y2) (mine had a purple)); Indoor unit to thermostat install 7 wires, which following below. red (Rh) blue (C) yellow Y1 Cooling stage-1 Gray Y2 (Purple Y2) Cooling stage-2 Green (Fan) white (W1) Heating stage-1 brown (w2) Heating stage-2 If you don't want to rewire, I recommend to get CTK04 thermostat, which will be fine with your old wiring.

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.