[GregR]

Keep in mind that the $2000 federal tax credit only applies to improvements to an existing home, not new construction (Energy Efficient Home Improvement Credit | Internal Revenue Service).

Originally Posted by jrref

If you are building new you should have the option of the Carrier Performance base Single Stage unit, Carrier Performance 2-Stage unit and the Carrier Infinity Variable Speed unit. The difference between the systems is SEER efficiency, 16, 18 and 24 SEER respectively and temperature and humidity control. The Carrier Infinity will control the temperature and humidity the best and qualify for the $2,000 Federal Tax Credits which ends this year. So, if you have a choice and can affort it, get the Carrier Infinity. Just remember with these models they will try and add on all kinds of air purification extras such as UV lights, etc.. You don't need them and can always add them later. Just get the system without all the accessaries. As far as mold, generally you shouldn't have to worry but I can tell you with my Carrier single stage base unit, my hepa filters would get some mold over time but with my new Carrier Infinity Variable Speed system, the humidity stays exactly where I set it and no more mold issues. Why is this? Because with the single stage unit, when it cools it removes humidity so depending on how long it runs will determine how much humidity it removes. It will vary the temperature as much as 3 degrees to try and hit the humidity target you set. With the Carrier Infinity variable speed unit, once it reaches the temperature set point, if the humidity set point is not reached then it will run in "dehumidify" mode which is at a very low speed to remove the remaining humidity without lowering the temperature as much. That's the big difference beyond efficiency between the systems. The basic runs 100% On and 100% Off and the Infinity runs variable from 20% to 100% only at the speed it needs.