Ruud Achiever 9 is 21-years old
The central ac unit I have is a 2 1/2 ton Achiever 9 unit, built and installed in 1990. I bought the ac unit with the house in 1998. It has been working pretty good for a 21-year old central heating and conditioning unit. I've had to have serviced each year and it needs about 1 to 2 pounds of R-22 added.
I guess a small leak in a weld or something at the evaporator core. Last year it did burn the wires at the compressor because the run capacitor was going bad. Items replaced and runs fine since then. I will replace the whole unit, one of these days, I'm just waiting for a fatal failure.
I'll replace with a SEER 13 2 1/2 ton unit. Everyone has good and bad things to say about all the brands, but the biggest factor "I think" is finding a great installer.