A ductwork system, especially in new construction with lowest cost mechanicals, is not going to be sufficient for a 3 ton unit. The variable speed blower will try to overcome some issues, and could cause more noise. If this company neglects this important aspect to the system, look elsewhere. But they are quoting you a nice system (good to see they are using the best matching indoor unit with tin-plated coil--shows they know how to match a system well at least) at a reasonable cost considering all that's involved. You still should get a couple other quotes. Don't be afraid to explore other brands besides Carrier. The Infinity system is nice, and so is the zoning, but at a lower cost you can probably achieve similar if not the same results with another manufacturer using third party controls. Carrier has a big name in the industry with their Infinity system but I think there are good comfort solutions elsewhere as well worth looking into. The Infinity zoning is it's own thing, so would need to be incorporated into the Infinity control system. If they want to charge you $2.2k that better include full testing (with static pressure measurements taken) to ensure proper airflow with minimal resistance if they think the ductwork in place is proper. The 16.5 SEER heat pump is the 25HNA6. Little different unit because it has a different compressor type, which is actually preferable for zoning apps because it uses a 50% capacity on low stage rather than around 70% with the 25HNA9. But, I dislike the fact that the compressor must "stop" to switch stages, presumably giving it more wear and tear (my opinion, not sure if anyone else feels the same way).

Claire How did your old 2 1/2 ton pkg unit perform? You are certain it is a 2 1/2 ton? More is not better. Can cause short cycling, poor dehumidification in AC mode, and can shorten equipment life. not to mention higher operating cost. What size heat strip is quoted by Trane dealer? Without more info to support a 3 ton choice, I would stick with the Trane. IMO

"Bad" power factor does NOT increase the REAL actual power consumed, "REAL" or actual power is measured in kW, that's all you use and that's what you're charged for. If device(CFL) uses 80% of the power going into it, the power factor is 80%. Power factor is the Real Power divided by the Apparent Power. For example, 98 kW (Real Power) ÷ 100 kVA (Apparent Power) = 98%. Again, residential customers are charged only for the REAL Power actually used, not the Apparent Power sent, That's not our problem, it is for the utility, believe me if it was a significant amount we would be billed a fee for power factor. Factories are billed for power factor,power factor does require the utility to compensate a little bit, it's at a far, far lower level than would be the case if they had to make up the total difference between the actual power factor and a power factor of 1.We can and do ignore the power factor issues in residential, there would be no way to diagnose anything if no rules applied or reality unable to be qualified. To prove this point, I set up an experiment with CFLs vs. incandescent lights (resistive loads with a power factor of 1.0), and measured watts and volt-amperes delivered by my inverter. Then I measured the amps from my power source, a bank of L-16 batteries, which are DC sources wise to the tricks of reactive power....The low power factor did not require the batteries (or the utility) to produce any extra energy.

I am reading all these posts with interest as I have now received my first electric bill for a FULL month with my new system. I put in a Carrier standard blower 13 SEER 2 1/2 ton heat pump/AC system with Puron. It replaced a 20-year-old Trane heat pump/AC. It is certainly not an awful electric bill but I was hoping to see a little bit of savings: Oct 07 with 31 days, I used 612 KwH, and avg. temp was 71. In Oct. 06, also 31 days, I used 703 kwh but the average temperature was much cooler: 64. Since I probably used some heat a year ago and I have been using AC this month , I figure these are probably pretty comparable months. My bill is: $88.42. For the year-ago period: $83.37. The price per kwh now is: 10.86 cents per kwh; a year ago, it was 11.03 cents (this was back when we were getting that "reduction" from the enormously high bills, as those of you in Md. will recall). I work from home and so tho I have a programmable thermostat, I never use that function, just adjust. I keep the house as 76 (75 if it is truly awful out) in the summer and in the winter, 72 (again, the truly bitter cold will get me to aim for 73 or 74). I turn the AC off at night most nights and just use a ceiling fan; it is often off during the day as well since I work in the (almost always cool) basement. Nothing else has changed "electrically" here; my hot water, refrigerator, and other power uses are unchanged, nothing is broken, etc. Obviously, I did not purchase "high efficiency" system but I assumed all NEW systems are more efficient and hopefully a little less expensive to run. I guess this was a wrong assumption.