Here's the deal with the "16 SEER" and "19 SEER":
Its more of a marketing ploy than correct information. You see there is a institution that tests many upon many combinations of heat pumps and air handlers to find their "actual seer". What I'm getting at is that if you were to purchase the 19 SEER Infinity heat pump it is very unlikely that you're actually going to be operating @ 19 Seer. As long as 19 Seer was achieved with just one configuration using the "19 Seer" heat pump then Carrier can market it as such. Same goes for the 16 SEER and this is relavent to ALL manufacturers. My advice, go with the 25HNA6. For the difference in price you're not going to achieve that much more performance. Have you found a contractor yet? Good luck and kudos for going with Infinity
Attitude is greater than Aptitude