The addition is 2400 sq feet or the whole house with addition?

What kind of heat do you have now?

I going to "echo" a lot of experts here on the forum and say that you need to have a load calculation done first.

That will separate the serious, knowledgeable people from the rest. Take my word for it.......it is important. If you find yourself fighting them on doing one, then move on.

For example, if you oversize the cooling capability, then you'll increase your changes of humidity problems. On the other hand if someone picks something too low in output, then you'll be uncomfortable and have warmer areas in your home.

Once you have that, then look at what they are offering and the price. You really should have three quotes.

I can't tell you the number of times I've been "burned" by trusting someone who seems like the good guy down the street.

This post was edited by audiomixer on Tue, Feb 5, 13 at 19:49

Agree fully with audio, especially cooling load calculation, but might add since you live in Boston, I doubt whether you will need A/C for more than 3 months.
I personally would not pay extra for a 2 stage system.

A 2-stage AC can be very effective for lowering humidity. I find I am comfortable with a 78 degree setting with the indoor humidity in the upper 30s to low 40s.

You don't need to spend the extra money on an 18 SEER AC in Boston. The second option is the best value in my opinion. The 2-stage proposal seems over priced. As much as I like the 2-stage feature I would have a hard time justifying the extra $1850.

Ask if options 2 and 3 can be matched with a 3 ton air handler. You may be able to save a few hundred dollars with a small loss of efficiency.

I would interested in both the sizing of addition and how you plan to heat it.

As far as pricing, the best thing I can say is it is quite frisky and that would be an understatement. Lots of fingers in that pie!

IMO

My understanding is that the quote includes installing duct work for the AC. It is difficult to estimate the cost of that part of the installation.

Most general contractors know nothing about HVAC, so you need to really speak directly with the HVAC contractor and judge whether they are competent. I think you should get additional quotes. Don't be pressured into making a quick decision.

For Mike

Right or wrong, ductwork is cheap both labor and material. Installer should have no Bldg obstacles since this is an addition. Now what a dealerGC charges is a different story. And generally these ductwork jockeys are poorly paid as far as in the residential HVAC labor market. Insulation is cheap as well.

IMO

This may sound crazy, but the cost of the heat pump version is actually less money than the straight cooling 2 stage unit he quoted you. I thought i had a mis-print in my price book but the YZH36 (heat pump condenser)is almost $200.00 (at cost) compaired to the CZH36 (straight cooling condenser). Granted..im in the south and their pricing might be a little different than mine, but it sure wouldnt hurt to get a heat pump quote as well.
Hope this helps

Good suggestion by previous post...need to learn though how OP plans to heat this addition.

Waiting on a response to my question.

IMO

After feeling that I was being taken advantage of by high pressured sales people, on the advice of several friends I called Lowe's and a guy came out right away and gave me a free estimate and no pressure. I got a great deal on a Trane and I love it. Another thing that I love about it, is that everything is made here in the USA.

I live in the south and my home is 1850 square feet and I have a 3 1/2 ton unit and I don't believe you are going to get the best efficiency from a 2 1/2 ton unless you are installing two units. Please get at least one other estimate you home is too important to rush into a decision.

3 1/2 ton for 1850 sq ft?...

Wonder if load calc was performed?

Wonder what size you replaced?

If oversized, you will suffer in the South with poor dehumidification.

Sorry.

You should start your own thread rather than hyjacking another.

IMO