"Jay Stootzmann" wrote in message
news:XO%uf.685178$_o.38838@attbi_s71...
I currently have a relative high efficiency gas furnace and air
conditioning system.

The gas furnace exhaust is via a plastic pipe. Though the motors for the
furnace fan and the AC are not multispeed so they are not the highest
efficiency available but in 1991 they were pretty good for that time.

The furnace and AC are into their 15th year and it's my understanding that
the useful life of these items is usually 15-20 years.

I'm wondering at what point I should go ahead and replace my system? With
the price of Gas continuing to go up should I be looking sooner rather
than later?

When I replace it should I go with another high(er) efficiency gas furnace
and AC [location is north central Illinois]?

or Should I be looking at replacing with a geothermal system?

Any thoughts, comments, things to look for, etc.

Now is the time to do some research (O.K., I guess that's what you are doing
now). Ask your friends and neighbors who they would use to replace your
system. Call up at least 3 or 4 different companies and have them come out
and give you an estimate. Ask them the same questions you asked here. From
what I can gather from your post, your sytem is still in good working order.
That's good. That way you are not pressured into making a desicion.
Depending on the efficiency of the units you have now, you may not WANT to
change them out at this time. You may not get your money back in a
savings/cost scenerio. At least you can get an idea on the cost and
options....