-While building a new house recently, I was faced with the choice of a gas furnace or a heat pump to heat/air condition my house. I was confused about which one to choose.

Heat pumps use electricity to operate, and they function by using fluid and coils to transfer heat. A gas furnace (which obviously uses gas), heats the house by igniting the natural gas.

According to my architect, heat pumps are better for situations where you don't have a heavy heating load. Why? Because they do not heat the air as fast as a gas furnace does. Note that my HVAC contractor (in 2006) told me that the new heat pumps are much more effective than the old ones and that this is not an issue. I trust him, but I trust my architect more :).

Here in Atlanta, my architect advises using heat pumps on the top floor of your house where the rising heat has made the space warmer than the rest of the house anyway. The heat pump will not have to work as hard on the top floor, so it will be fine.

I have chosen to do gas furnaces in the basement and first floor and a heat pump on the second floor.

A related issue is venting: Gas furnaces produce carbon monoxide (and maybe other byproducts) that needs to be vented outside. Apparently, if you are willing to pay more for a higher efficiency gas furnace, you have a lighter venting requirement that may increase your options in terms of where the vent pipe exits the house.

I have found heat pump prices to be slightly less than gas furnace prices (your mileage may vary), and this is attractive in light of the high natural gas prices we are currently experiencing.

Former builder and instructor of "Save Time and Money in Home Remodeling" cont. ed. course at Emory University