My split unit York (NG furnace) was 25 years old if she was a day, but TN summer's been brutal and she was overcome. She's dead. Now what? Two general questions: (1) For a leaky 1936 house (5500 sf, 2x4 walls w/ no insulation in them, 1960s-ish single pane windows, giant un-flued fireplaces, severe leakiness all around), is geo an option? I like to think that since I use a lot of energy, I'd want to produce the energy as efficiently as possible. However, I'm also concerned that I'll be in auxilliary heat all winter and not see the savings that I might expect. I realize my bills would be drastically cut, but I also realize they better be because of the heavy payback of the system. (2) I got one quote back (waiting for the second). The one I got was VERY basic - 2.5 sentence description and (big) price. Is he waiting to see if I'm sticker shocked before doing any real work to properly measure/size the house? I'm reading on this forum that it takes some careful planning (and possibly NASA certification) to get a good system, and walking around looking for 45 min won't cut it. But, I also understand not wanting to invest a lot of time until it looks like it might pay off. Contractor has a good reputation here. Thoughts?