Your situation was the same as mine when we had our home built in 1977, heat but no AC. Had a unit installed the following summer, (we moved in Oct, and house is 1800 sq ft). We had a 3 1/2 ton put in, which lasted until 2010, when we had a new furnace and AC system installed. Our furnace is also in the basement, and there is NO, problem moving the air, although we do change vent position for summer and winter, as cold air drops, and heat rises. At 1500 sq ft, you would most likely need a 3 ton unit, a 13, 14 seer would probably work, BUT, if the humidity is high, I would check a higher seer, 2 stage unit, as the first stage runs on low, keeping humidity down, and when cooling is called for, the second stage takes over, this is probably the only mistake I made living in Chicago, when it is humid in the summer. If you subscribe to something like Angie's list, they can direct you to a good installer, friends of mine got a great installer from Costco, and it did not cost $5000, more like half that amount.

Sorry, I thought by matching we were talking about the refrigerate R-22 verses R-410a in the coils The coils will be First Co. Evaporation coils matching the existing air handlers I have. Apparently there is no AHRI reference number because First Co has not done any of the necessary testing. The dealer had told me this and that the system would not qualify for the tax credit. The third floor does not heat well with the present arrangement. All of the dealers have told me not to expected much cooling on the third floor. I did not question him as to what the "better options" might be.

Thanks for the response! I got another bid for $5900, though the guy didn't put anything in writing, so I don't know if it was apples to apples. What gets me is that originally the guy was going to charge me 4950 for a 3-ton 13 SEER but when I mentioned I had a mailer/flier from his company, he quickly shifted gears, said okay after insisting that I show him the flier and said that he would have to charge me $250 for "modifications to the plenum." I am also not sure the furnace is one of their better ones for Ruud. Seems like their cheapest. I am located in the San Fernando Valley (part of Los Angeles), which is very hot most of the year.

Home warranties are not worth the paper they are printed on. Ask anyone that's tried to file a claim. Well, my mom keeps renewing her home warranty because she has filed several claims and has had good experiences. When we sold our house last year we offered a home warranty because the house was 22 years old. There was an issue with the swimming pool during inspection, and rather than deal with it at the time we extended the warrantly to include the pool. I have been notified by the warranty company that the new owners have used the warranty service at least twice. Once for the pool and once for the heating system. We went with American Home Shield, which is the company that my mom uses. If you do go with a home warranty DO make sure that the new 13 SEER units are covered. Have the seller pay for an HVAC guy come out and check it. I like the idea of heating up the inside personally. Didn't you read the posts that said that running the air conditioner in cold weather could damage the compressor?