"trailer" wrote in message
My house was built in 70s and I have added insulation in the attic. It
has
about 2200 sq ft living area. My highest electric bill this summer was
$350 (electric only).

Is it worth replacing the AC and/or the furnace with new units? Depending
on the costs, I would strongly consider upgrading the SEER.

Thanks.

Run the numbers. Since your house has additional insulation, it may be
possible to get the same or more comfort with a smaller unit. You need to
find a competent installer that can properly size (Manual J) the unit and
figure operating cost comparisons. We don't know your climate or your
electric rate so we can't decide for you.

OTOH, if it breaks it is probably not worth investing a lot of money in
repairs. At least you'll be ready to make the right choice if it does.