I'm going to be in this boat soon. Have a Trane AC unit which is original to this 1980s house.
We lost the blower unit a couple of summers ago due to what I think was a lightning strike a year or two before that. The same lighting strike took out a ceiling fan, some florescent ballasts, and a home theater setup.

Anyway; I've been basically wondering to myself when the ideal time is to replace my unit for optimal savings. I don't want to be under the gun; but the clock is ticking ...
Does anyone have any real advice if there is a good time to price and execute a replacement? Winter? Fall? never?