[KarlInOhio]

Do you have any suggestions on buying one? My AC is long overdue for replacement, and I was going to check on the price of an AC/Heat pump because it might be cheaper than running the gas furnace this winter. If it's not to expensive, a ground source might be a good alternative.

[Eric in the Ozarks]

The unit is called a Water Furnace, made in Indianapolis. There are four 200 foot wells drilled (under our driveway) with a sealed liquid ground loop running from the wells to a heat exchanger and compressor (the Water Furnace) inside. The system collects heat from the house into the incoming liquid which is 59-60 F, so its easy to make chilled forced air. In the winter, the unit pulls this same liquid in and bumps it 10 degrees electrically for forced air heat on the second floor. The floor in the main level is tile and has radiant in-floor heat, also from the Water Furnace. This works best for new construction but I'd take a look if you don't mind the up-front cost (a little pricy). This system will also make hot water for showers.
Good luck.