Replacing My HVAC System
Hi - we live in Atlanta where it gets really hot in the summer and not too cold in the winter. We have two story house and need to replace the HVAC for the main level. We replaced the HVAC for the upstairs two years ago. Here are some details:
Our main level system is a Carrier that is 15 years old. It is a 2.5 ton A/C Unit with an 80K BTU furnace. I do not know the SEER Rating because it is so old.
Contractor 1 recommends a 3 ton Trane XR15 with matching coil and a XR80 Furnace. When asked about a Variable Speed furnace, this contractor said it is a waste of money to have in Atlanta.
Contractor 2 recommends a 2.5 ton Trane XR13 with matching coil and a XV80 Furnace. This contractor was insistent on us using the variable speed furnace and didn't want to give us a quote on the XR80.
Do any of the pros have an opinion of which one of these would be a better fit for our house?
Of course correct sizing is most important.
One dealer quotes a 3 ton condenser, the other a 2 1/2 ton condenser.
You do not specify the size of furnaces quoted. I prefer the XV80 furnace and if not that model then the XT80 furnace that has high eff blower.
What size living space is main level? How is home's insulation and building qualities?
Tigerdunes - Thanks for the quick reply.
The furnaces that were quoted were both 80,000 BTU
The total living space is 3700 square feet and I would say that the main level is 1700. However, our living room is a two story living room so the ceiling is very high. In the summer, our house gets pretty hot in the morning because we have a large window facing east. 90% of the window is covered with solar shades, but the other 10% is impossible to cover due to the shape.
The insulation in the attic is R-60 fiberglass. We had that blown in two summer ago and it really helped out. Building quality of the house is also is good shape as the house is only 15 years old.
If we go with Contractor 1, would it be worth it to ask about the XT80 furnace so we get the dual stage heating?
Last edited by AtlantaRes73; 05-02-2012 at 04:41 PM.
I'd go with the XV for vairable speed and 2 stage for heating. IF the main level is 1700 and it's fairly well sealed and insulated, I suspect 2.5 Tons is plenty and will remove humidity well with long run times. On that same note, a home in Atlanta that only needs 2.5 Tons of cooling will likely only need 60k BTU's of heating... if even that, even on a 1st floor. Yopu'll get longer run times and more even heating throughout the floor.
The vairable speed will also allow you to dehumidify on demand if you get a thermostat that can control humidity. This will make it more comfortable and cheaper to operate since you can keep the temp higher.
Ultimately a load calculation will determine what size you need.
I had an XV80 and it heated very nicely and evenly. I miss my 2 stage furnace for sure. Not as quiet as a sealed combustion condensing furnace. But in your climate that probably a waste of money since your heating season is so short.
No sense in going with #1. His XR15 with standard blower will give 13.5 to 14 SEER and cost you lots of money up front.
#2 with the XR13 and XV80 will end you up around 14 SEER for lots less money for the A/C part of it. The variable speed furnace can be set up for extra dehumidification ability, a nice feature in your climate.
I had an XV80 for 15 years, never touched it.
Thank you for everybody's insight and advice. I talked to contractor #1 some more tonight and got him to give me a quote on a XR13 with an XV80. He gave me that as well as a quote on the XR15 with XV80. The numbers were significantly better than contractor #2 so we have chosen contractor #1. One of my friends has used him to install two systems and several of his neighbors have also used him so he is highly recommended.
You need to make certain those XV80 furnaces are sized correctly. I suspect you are being oversized.
And you want true two stage thermostats for best operation, not to be staged off control board timer.