Installed central air conditioner in our vacation home
I bought a 5 ton, 15 seer rating central air conditioner about a year ago and kept my old furnace unit (one year old). The central air conditioner units cost me more than $7,500. I'm pretty sure it was close to that. I don't remember the actual prices.
I’m not sure about the brand. The central air conditioner units was not install in the house we live in. It was on our vacation home. The house was built in 1967 and is about 2500 sq ft.
The house has a lot of insulation in attic, wall, and all the doors. However, not single windows have been replaced with energy efficient ones.
A builder told me about 20 years ago that he built this house (vacation houses) to a standard that would cool the house down up to 35 degrees.
Then we got a horrible summer where 115 - 120 degrees were not uncommon. So our vacation houses could only cool off to 80 to 90 degrees! Our nights do not cool off too much, so the low temperature we had on most days in the summers are about 85 to 95 degrees!
My understanding is that an AC unit needs to be sized very carefully. Considering windows, size of home, how it sits relation to sun and trees, and of course your local climate.