Heat pumps

[Spook50]

Right now we've got gas forced air heat and central air conditioning (no idea what size of capacity of air conditioner. Just haven't looked into it). I've got about 5 years of life left in the furnace based on what the home inspector told me, and I've been doing some research on heat pumps for once the furnace needs to be replaced. Any of you guys use one? If yes, how do you like it? Worth it to convert over when the furnace (or A/C) needs to be replaced?

 

[firetruck41]

I am fairly certain that up here, Natural Gas is still cheaper than running an electric heat pump. I bet your home inspector doesn't know much about furnaces, and you could keep yours going a long time, if you wanted, they aren't complicated and parts are readily available. If it actually needs replacement, I would probably just replace with a high efficiency gas furnace.

If money were no object, it would be cool to install a heat pump and gas furnace (could be done), and then figure out a thermostat interface that would use the cheapest/most efficient energy source at the time the thermostat calls for heat, based on energy cost, set temp, outside temp, humidity... There is probably some x10, or home automation program, or thermostat that could be configured to do this... hmmm... Of course all this efficiency, would cost way more than the energy saved, but neat, nonetheless.

 

[-Spike-]

Heat pumps are popular down here- 'cause it never gets really cold. For anything prolonged under freezing, a heat pump is worthless. I have one, but wish I had gone with an A/C unit with a gas pack.

 

[wob]

Heat pumps are popular down here- 'cause it never gets really cold. For anything prolonged under freezing, a heat pump is worthless. I have one, but wish I had gone with an A/C unit with a gas pack.

That's what I had in my old home. I replaced it with an electric unit, which blew my old gas pack out of the water in terms of heating performance and monthly operating costs. But, I got all of my ductwork replaced at the same time.

 

[LandCruiserPhil]

Heat pump - compressor runs twice as much per year
Most expensive part of Heat pump/AC unit is the compressor
Heat pump is an AC unit that runs in reverse to make heat
On cold days Heat pumps outside coils freeze, compressor needs to run in AC mode to defrost coils to make heat = less efficient
Heat pump are not as efficient as gas - Same thing goes for a cloths dryer and water heater
Electric companies push heat pump due to the excess power they have in the winter

 

[-Spike-]

That's what I had in my old home. I replaced it with an electric unit, which blew my old gas pack out of the water in terms of heating performance and monthly operating costs. But, I got all of my ductwork replaced at the same time.

It's also possible that gas is cheaper around here due to much less demand, while electricity is relatively expensive.

 

[wob]

It's also possible that gas is cheaper around here due to much less demand, while electricity is relatively expensive.

I dunno, but winter bills absolutely killed me in that old house.

 

[Trollhole]

In milder climates a heat pump is more efficient. In most Southern states a heat pump is the way to go. That being said gas prices play a big role. Here in SC gas prices have gone through the roof in the past 5 years. Back then it made sense to run gas in the winter. Now not so much.

When my A/C unit crapped out on my upstairs I Replaced the unit with a heat pump. I kept the furnace. It's not a very efficient one but the fact of having a duel fuel system made up for the fans limitations. I've now cut my milder climate bills almost in half using the heat pump. And when it gets below 36 I have it set to switch over to gas. Makes for a nice comfortable room.

Going duel fuel is not that expensive. Maybe 400-600 more for the heat pump and maybe 100 dollars more for the thermostat that controls it. You will make that up in cost savings over a couple years. That all depends on your gas prices in your area. When anyone tells me their A/C unit went out and they have a furnace that is in good shape I tell them to go dual fuel.

From the looks of it your states gas prices are lower than ours. So this will play a big part in recouping your duel fuel investment over a longer time. That being said another aspect of duel fuel is you have the choice. If gas prices rise you can always set it not to cut on as much.

http://www.eia.gov/oil_gas/natural_gas/restructure/restructure.html

 

[SunTzuMD]

The place we just bought has a brand new lennox 'dual fuel' system. Runs the heat pump until an outside ambient temperature of 45 degrees (adjustable) and then the propane furnace kicks in. The owner installed it just before we bought it. Supposed to be highly energy efficient.

To my understanding the heat pump is more efficient in moderate temps and the furnace is more efficient at lower temps. So you are trying to tap into the peak efficiency of both.

I'll let you know how it works out this winter.

 

[LandCruiserPhil]

Something that seems to be overlooked, with a heat pump your compressor run twice as much, lasting 1/2 as long verses a gas pack. The most expensive part on the unit.

 

[Trollhole]

Something that seems to be overlooked, with a heat pump your compressor run twice as much, lasting 1/2 as long verses a gas pack. The most expensive part on the unit.

May have been a problem 5 or more years ago but with the newer compressors (scroll) reliability isn't really and issue. They last a really long time. I'm willing to be more fans give out first before the compressor.

 

[Woodsman]

I have a heat pump on my small (less than 1,000 sf house) and though it is better than the previous all electric furnace with no AC, it is not efficient below say 20 F.

My parents have had geothermal (ground source heat pump) since 1990. They were an early adopter of this technology in our area and just had a new one installed last year. The new units are less expensive than the first one was and are much more efficient. Now, all of our neighbors have have switched over. We recommend WaterFurnace brand.

My sister owns a 6,000 sf ski chalet in British Columbia. It was the first home at Big White to have geothermal. It was a groundbreaker as the builder/owner was a heating/AC contractor and knew what was best. They brought in drills and bored straight down into the rock for the lines whereas here in Indiana we generally use loops in the yard. Now, except for the low end of the market, all of the new places at Big White are built with geothermal.

I plan to add onto my house within the next couple of years and plan to add geothermal as well. I will take the heat pump and move it to my woodworking shop so I have better AC than I do now.

 

[cruiser88]

And I bet the ducts/heat pump was sized proper unlike most. However any temps below 34(I say 34 because efficiency is out the window) and heatpumps become worthless as said above.

That's what I had in my old home. I replaced it with an electric unit, which blew my old gas pack out of the water in terms of heating performance and monthly operating costs. But, I got all of my ductwork replaced at the same time.