Robinrs said:
She's already had it checked out by two sources, both agreed it was gone. She bought the house 2 years ago but the AC unit was the original, at least 25 years old.
It's not surprising the unit is shot, then. We had to replace one of our air units last summer, and it was maybe 23 years old or so. We still have a smaller unit about 25 years old that operates our upstairs. It will have to go in the next 3 or 4 years, I'd say.
Be prepared to spend at least $3,500, if you have to replace the indoor unit as well as the compressor outside.
Newer units, I think, use Puron now instead of freon. It's supposed to be better for the environment.
We spent about $4,500 and got one that (sort of) controls humidity levels in the house. That makes a nice difference. It's not a humidifier/dehumidifier, but basically uses the fan to blow humidity in/out depending on the season. Ours also has variable speed fan settings, so if it has to heat or cool the temperature by, say, only one degree, it will only blow the fan just enough to accomplish this change. It's more efficient than the fan going full bore to cool or heat one degree, when that speed should only be used if you have to heat or cool 2 or 3 degrees at once.
Our electric bills went down maybe an average of $50 or so since we installed it. It's not as much savings as I'd hoped, but it counts. Our old unit was on almost constantly and still couldn't get our air the way we needed it. This one is much quicker to heat/cool, so it can shut itself off more of the day, unless the temperature outside is at an extreme. With outside temps right here now in the upper 70s for highs and 50s for lows, it's not on all that much.
Next step for us, hopefully, in the electric company battles: tankless water heaters!