ShockMe,
Do you just run an 8/2, or do you go by the nameplate on the unit? Remember, some high efficiency units may only require #14 or #12. With the high price of copper, you may want to rethink this approach. Simply going by the tonnage is not a good method in my opinion.
Case in point: Once upon a time, I had no clue how to size the circuit for an AC unit. The AC guy said "Run a 10/2 and put it on a 30 amp breaker." A few years later, when I learned the right way, I read the nameplate on the unit: Min fuse breaker- 20 amps, Max fuse/breaker size - 25 amps. I removed the 30 amp breaker and installed a 20. Lesson learned.
