Heat pump vs central air (Charlotte: house, to buy, live)

[st3lan]

Hi - need some advice here... We just recently moved to CLT from Michigan and are looking at a home that has a heat pump for heat and a/c vs a gas furnace and central air. Coming from the north, I am not familar with them. Do they sufficiently cool down the home in these hot/humid summer days and warm in the winter? Currently we are in a place that has a furnace and central air and keep the temp at 73- 75 in the summer and 72-76 in the winter. I have googled this and am getting mixed results on it's efficiency on cooling a home and keeping it nice in warm even when temps dip below 40 in the winter.

[running123]

We have 2 heat pumps for our home and they seem to work fine. We keep our temp at 70. We don't have a gas drop so that was not an option for us. I personally wouldn't think to much about either unless I was building a home, then maybe I would do more homework.

[Native_Son]

if your home is very energy efficient a heat pump may be ok.

Otherwise I'd go with the gas pack. People suggest heat pumps a lot, but only because they are a little cheaper to buy/install.

[SouthernBelleInUtah]

Heat pumps do a poor job of handling humidity and very hot weather. I have had 2 when I lived in the South and replaced them both w/ac. You may be more uncomfortable since you are coming from a northern location. Read Consumer Reports for more info (available at libraries or online). Heat pumps are designed for areas that don't get too hot or too cold as they can't handle either extreme. You can only get so much difference from the outside air.

[lumbollo]

You will want to make sure it is a very new heat pump. It does get cold enough in Charlotte at night in winter where these things don't work very efficiently. I had a heat pump in my last house and couldn't ever get used to the heated air coming out being cooler than skin temp.

As far as cooling is concerned, I don't think there is any issue, but I have heard that a pure AC might be more efficient. If I had my choice, as I did in this house, I would take AC/gas over heatpump.

The only exception to this would be if you got a ground source heatpump. They do work well, and you can't beat them for saving money, especially if you also use it in conjunction with heating water, but they are very expensive. I had briefly looked into one of these when I had to replace one of my systems, and while I liked the specs and how it worked, I just couldn't cost justify it.

[Plan R]

As far as cooling, I don't think there should be any difference in power between heat pump and A/C. It's the same thing, it's just that it can reverse the flow of heat from inside out to outside in.

We have heat pumps up and downstairs. Our bills are MUCH lower in spring & fall as compared to before, when we only had a high efficiency gas furnance. These temps -- 40s through 60s -- are perfect for heat pump. Have read that it's something like 3x as efficient as gas in this range. Charlotte has lots of weather like this, so it's a good fit.

As far as cooling, I think that heat pumps can be just as efficient as A/C -- again, there's very little functional difference between heat pump and a/c. I think our unit is 15 or 16 SEER, and they go higher.

Some people complain about temp of air blowing from vents with a heat pump. It's not hot like gas, just lukewarm and can feel cool on skin. Maybe we don't have any registers where it blows directly on you, but it's never bothered me and more than worth it for the energy saving in my book.

To keep a house warm when it's very cold, heat pump has to have electric heat backup aka heat strips -- think heating elements, like a toaster. It also has to periodically heat the outside unit up, because it will freeze in really cold weather.

Really, the most efficient is hybrid heat, where you have heat pump backed up by high efficiency gas furnace. The furnace turns on when the temp gets low enough that it's less efficient for the heat pump to pull warmth from the air, somewhere around 40 degrees. More expensive upfront, so you have to run calcs based on how long you'll be in the house. We have this downstairs, upstairs is heat pump only.

[Charlotteborn]

I lived in a house with heatpump heating ONCE - never again!!!!!! It is too cold - gas heat for me!!!!!

[thejersey3]

Go with the heat pump unless you were considering a multi-stage gas furnace. In cooling mode there will be no difference between heat pump and AC, assuming the units were sized and installed properly. In heating mode you won't get the blast of 130 degree air you may be familiar with on a standard gas furnace, but you will get lukewarm air and MUCH lower utility bills with the heat pump. Maybe not as much difference in temperature or cost if you compare to a multi-stage gas furnace running at the lowest stage. Bottom line with operating cost is natural gas follows the commodity pricing which have been high the last 5 years (although dropped somewhat this year), but electricity is more highly regulated, and relatively inexpensive here.

If you really want to take a step up invest in a geothermal heat pump which is what I have. My TOTAL utility (electric) bill to heat, cool, and operate a 3500 sq. ft home is $130/month on average. You can do nearly just as well with a multi-stage conventional heat pump also.

[movin-on08]

what you must know is that heat pumps work based on a difference in temperature between inside and outside. In the summer, heat pumps rule. In the winter, heat pumps will not provide that "hot air" that you are used to from a furnace (I am from MI too). The heat pump will run much longer in cooler weather and the temp of the air coming out of the vents will seem to be cold. It really isnt. The air coming out of the vents is warmer than the setting on the t-stat, but cooler than skin temp. Thats why it will feel cooler.