Our heat pump is an American Standard Heritage 16. It has a 2 stage compressor. The set point for the electric strip heaters is 24F. SEER 17 HSPF 9.2.
Wood vs...Heat pump?
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And unlike the minisplit systems that can have hspf ratings well into the teens, the conventional ducted heat pumps look "normal" in your house.
With those electric rates I would not be that concerned about strip heat in your locale. Most folks who complain about heat pumps and strip heat pay twice kw/hr that you would be.
Yes, ours was installed 8 yrs ago when most of the mini-split systems were not available locally. It was leading edge for a central system. Only Sanyo had a ducted mini-split sold in our region and we would have been the first to try it. Technology and availability of higher efficiency units has greatly improved since then. Still, for our climate our system works quite well.
planner steve
Burning Hunk
Highbeams last point is key. While we all love heating with wood, most people who might eventually buy your house won't. You sound like this might not be your last house so resale value is important. I have a heat pump and insert in your climate. I love the AC right now. One can heat with wood for lower cost here, but only if you hunt for very low cost wood. Your home configuration also might not work well with wood stove, might be hard to get heat between levels. Go with the heat pump.
I updated my old electric furnace/heat pump a few years ago with a Carrier. The biggest difference I've found is newer heatpumps are efficient to 0 degrees. The furnace itself hardly runs. I also burn wood all winter long to help out.
Hope this helps,
freebe
Hope this helps,
freebe
Osagebndr
Minister of Fire
I have a Trane setup and burn wood all winter and it never runs ( on purpose). A $250-300 heat bill is awesome , mine runs $650-900 depending on the temps with just the furnace thus I burn wood and I pay $220-280 monthly
NickDL
Burning Hunk
Our own personal opinion is that we hate having a heat pump. Our last home & current home have one and it doesn't even compare to gas heat that we grew up with. We feel that our house always feels a bit chilly with the thermostat set at 68°. Our bills this winter were as high as $600 in Pennsylvania. I forget what we pay for electric, but it is a pretty good price.
If you have a propane fireplace, then I would consider having the heat pump with a propane backup for those nights when it's really cold.
A propane fireplace can put out a good bit of heat. We used to have one in the old house & we used that instead of the heat pump, but boy did it cost us. Propane was expensive for that use, but so much warmer.
As others have said, look at resale value down the road. Good luck.
If you have a propane fireplace, then I would consider having the heat pump with a propane backup for those nights when it's really cold.
A propane fireplace can put out a good bit of heat. We used to have one in the old house & we used that instead of the heat pump, but boy did it cost us. Propane was expensive for that use, but so much warmer.
As others have said, look at resale value down the road. Good luck.
A lot of folks back east have older, inefficient heat pumps. The newer units are quieter and better. How old is your heat pump Nick and what is its heating efficiency rating?
JA600L
Minister of Fire
I realize the new ones are much more efficient, but how does that help the problem of the outside air being colder then the evaporator? The evaporator needs to extract heat from the air and can't freeze the lines.
NickDL
Burning Hunk
Our current unit is at least 6 years old, we've been in this house for only 4 years. I'm not completely sure of it's efficiency off the top of my head, I believe that it's a middle of the road system when I looked it up. The unit is quiet and works. As far as air conditioning, it works really well. The house just never has that warm toasty feeling, unless of course the strips are heating the house, then we're talking expensive.
Our old home we put in a Trane 14 seer unit that worked really well, especially for A/C. Again, it just didn't have that warm toasty feeling that we grew up with in our gas heated homes.
http://cshvac.com/2011/12/16/myths-about-heat-pump-heating/
The compressor technology in older heat pumps was very inefficient and blower speeds had to be at optimal levels to try and keep efficiencies as high as possible. The end result was lukewarm air and moderately high electrical costs at best that increased dramatically as temperatures dropped.
Today’s more efficient compressors, variable speed blowers and newer refrigerant allows us to have high efficient heat pumps and a great deal of comfort too. Modern systems use high efficient compressors that use a fraction of electricity as older models. They also use a newer refrigerant which does a better job of extracting heat from the air outside even at very low temperatures. Then with variable speed blowers the system can slow the air down to allow it more time to pick up heat from the heat pump and make the air warmer. These systems will take this a step further and slow down the air proportional to the outdoor temperature to make sure the temperature out of the vents stays high even at low outside temperatures (Carrier calls this ComfortHeat).
The compressor technology in older heat pumps was very inefficient and blower speeds had to be at optimal levels to try and keep efficiencies as high as possible. The end result was lukewarm air and moderately high electrical costs at best that increased dramatically as temperatures dropped.
Today’s more efficient compressors, variable speed blowers and newer refrigerant allows us to have high efficient heat pumps and a great deal of comfort too. Modern systems use high efficient compressors that use a fraction of electricity as older models. They also use a newer refrigerant which does a better job of extracting heat from the air outside even at very low temperatures. Then with variable speed blowers the system can slow the air down to allow it more time to pick up heat from the heat pump and make the air warmer. These systems will take this a step further and slow down the air proportional to the outdoor temperature to make sure the temperature out of the vents stays high even at low outside temperatures (Carrier calls this ComfortHeat).
A lot of heat pumps are optimized for cooling and only so so for heating. It's important to select one with excellent heating efficiency if that is the primary task. Ours does fine down to 24F. There are better units now on the market. For that warm and toasty feeling we use wood.
JA600L
Minister of Fire
Mine is 8 years old as well. I really think it's a matter of your climate. Where I live most of the winter is well below 24f. A lot of it is in the single digits and teens. In this kind of a climate you just can't expect much out of a heat pump. On a 0 degree morning it simply doesn't work.
For sure they are not for all locations. The OP is in Western OR where heatpumps work well. A modern high efficiency heat pump will work well down to around zero degrees. Ours is decent, but nothing compared to what good mini-splits can do. I checked on a local old farmhouse that I recommended get a heat pump when it was 14F outside. Inside it was a comfy 72F with their Fujitsu unit quietly cruising along.
Not sure about the Carrier central AC mentioned earlier but that looks good on paper too.
Not sure about the Carrier central AC mentioned earlier but that looks good on paper too.
I'm late to the party, but vote for some sort of heat pump, but don't see a big rush. In Western OR even a basic unit (properly sized and installed) will get a seasonal COP of 2.2-2.5, meaning it will cut that electric bill in more than half, but the savings might not be that compelling.
One BIG question for the OP is the size....how many 'tons'? How did the installer estimate the size needed? A lot of folks who complain 'my heatpump doesn't work below 32°' actually have an undersized unit.
Re the $6500 cost...that's the cheapest I would get here for a 3-4 ton install with preexisting ducts, but I live in a HCOL area.
With the mild climate (what are the HDDs?) and cheap (and green) electricity, it might be a good idea to check the financials. If the OP is spending $1500/year on elec for strip heat, the HP might save $800/yr, and then needs 8 years to pay back. And it might last 10 to 15?
Its just as possible that the place could benefit from some air-sealing (probably needed) and insulating (might not be needed). This could drop the heating bill 30-50%, depending on the vintage of the house (??), and would cost less than $6500 I would think. After that work is done, collect a season of heating bills with the elec strip, and see if a single mini might cover the house (with an install cost closer to $3k)
IOW, its possible that $3k for energy eff work and $3k for a mini might drop your heating bills by 70-75%, and pay back in 5 years and in greater comfort. The ductwork blower could be used for air circulation if needed.
One BIG question for the OP is the size....how many 'tons'? How did the installer estimate the size needed? A lot of folks who complain 'my heatpump doesn't work below 32°' actually have an undersized unit.
Re the $6500 cost...that's the cheapest I would get here for a 3-4 ton install with preexisting ducts, but I live in a HCOL area.
With the mild climate (what are the HDDs?) and cheap (and green) electricity, it might be a good idea to check the financials. If the OP is spending $1500/year on elec for strip heat, the HP might save $800/yr, and then needs 8 years to pay back. And it might last 10 to 15?
Its just as possible that the place could benefit from some air-sealing (probably needed) and insulating (might not be needed). This could drop the heating bill 30-50%, depending on the vintage of the house (??), and would cost less than $6500 I would think. After that work is done, collect a season of heating bills with the elec strip, and see if a single mini might cover the house (with an install cost closer to $3k)
IOW, its possible that $3k for energy eff work and $3k for a mini might drop your heating bills by 70-75%, and pay back in 5 years and in greater comfort. The ductwork blower could be used for air circulation if needed.
The coolant is not water. It won't freeze in the lines. All that has to happen is that the evaporator has to be able to see coolant colder than the outside air so that the coolant is warmed by the outside air. That means if the outside air is 0 degrees, the coolant needs to be below zero in order to be warmed up. These things work well below zero, some down into the negative teens.
We're bumping into a marketing/business barrier and not a technological barrier as far as low temp heat pumps are concerned. When you can run a minisplit heat pump at 100% output to 0 degrees F, but most conventional heat pumps revert to backup heat near 20 degrees F you know it is just because the conventional heat pump guys haven't applied the technology yet.
There will also come a time when some smart guy successfully applies this technology to heat water for boilers and domestic in North Aerica. They do it in other countries using high pressure CO2 as the coolant.
JA600L
Minister of Fire
It won't freeze in the lines but it can freeze the condensation on the outside of the evaporator. I realize there is a lot I don't know about modern heat pumps. I enjoy heating with wood anyway. Maybe someday I will upgrade the heat pump. It's hard to justify when my electric bill hits only $75 a month in the summer and around $50 in the coldest parts of the winter burning wood.
Indeed. Which is why they run defrost cycles below 35-40°F outdoor temp. This eats 20-30% of the efficiency, depending on the engineering and settings of the unit.
Base charges don't matter if none of his alternative options avoid them. He pays them regardless of how much or little electricity he uses.
I estimate his normalized heating cost for the various options as follows, including duct losses:
Electric furnace ($0.065/kWh, including duct loss) - $24 / million BTU
Propane room heater ($2.50/gallon, exhaust losses only) - $29 / million BTU
Heat Pump ($0.065/kWh, 2.0 average effective COP, including duct loss) - $10 / million BTU
EPA rated wood stove ($200/cord douglas fir, delivered split or value of time to C/S/S) - $12 / million BTU
You can see from these estimates why my goal is to burn wood whenever the temperature gets cold enough my auxiliary heat kicks in. In that scenario, the comparison is effectively against the electric furnace cost, not the heat pump cost.
This is one of the most common complaints with heat pumps, even newer units with variable speed blowers. The issue is that although the air coming out of the registers is warmer than the room air by 20-25 degrees, it's usually still cooler than body temperature (85-90 degrees vs. 98.6 degrees). This means the slight breeze from the registers feels cool, and that sensation of coolness tends to persist even after the heat pump shuts off. In contrast, the air coming out of the registers from a furnace will be more like 110 degrees, so being above body temperature it feels nice and warm.
As a result, you usually don't have the same comfort level with a heat pump unless you turn the thermostat up a degree or two relative to what feels comfortable with a furnace. It's still more efficient, but that does cut into the efficiency slightly.
That said, I throw another vote to the OP in favor of the heat pump. Even accounting for the times the backup heat strips turn on and heat lost through the ducts, a total seasonal effective coefficient of performance of 2 or better (half the heating bill) should be achievable even with a single stage heat pump. $6500 sounds pretty good in this region. My 2 ton Goodman heat pump came to $6900 including Washington sales tax and one of the better Honeywell thermostats. That price in the Seattle area gets you an installer who cuts a few corners.
Worry about the wood stove later. Once you do have a chance to return to wood heating, I think you'll like the convenience of the heat pump complemented by the cold weather comfort of the wood stove.
For an anecdotal experience: My electric rate is 9.5 cents/kWh (no base charge). I'm in NW Washington, so the weather is similar. My house is 1800 square feet, moderately insulated with basic vinyl double pane windows and 2x4 construction, although I've got some insulating left to do. My peak winter bills have been about $150 per month over my minimum summer bills, with the thermostat usually at 68 degrees when we're home. I've been intending to shift more of my heating to wood, but due mainly to being very busy, I only burned 1/2 cord last winter.
Since the alternative is worse - an iced over heat pump would lose far more efficiency - it's hardly worth discussing how the defrost cycle affects efficiency. It simply comes with the territory. The main lesson is to compare the HSPF ratings, which attempt to account for defrosts, rather than the SEER rating.
Agreed. BUT, when using the HSPF to compute expected energy costs (since the units of HSPF are kBTU/kWh), keep in mind that your actual HSPF may be higher or lower than the rating, depending on whether your climate is warmer or colder than the reference climate. That reference is roughly the same climate as Atlanta, GA (~1200 HDD). Where I am (~4000 HDD), observed HSPFs are roughly 20% lower than the nominal rating.
I can attest my heat pump will put out warm air to 10 below but its capacity is limited. Its definitely something you set and let run versus trying to adjust over the course of a day. The air is definitely warm not hot. My power is "free" from net metering but as the HSPF drops there is some point where some folks probably would elect to use radiant space heaters over the mini split.
One thing to consider is that it is quite noticeable the amount of defrost cycles when the relative humidity is high in cold weather. During cold dry weather, I rarely hear a defrost cycle but during damp wet snow events I hear it defrosting far more often. There are optional baffle structures that are available on some models to keep snow from blowing on the coils but they do nothing for damp air on supercooled surface. Given the Northwest reputation of a wetter climate, I expect the useful low temperature range may be a bit more limited.
I currently have one 12K unit that heats my fairly tight 2 story house down to about 30 degrees. I plan to replace an older mini split AC unit with heat pump version on my second floor office and use that to heat the office rather than heating the entire house.
One thing to consider is that it is quite noticeable the amount of defrost cycles when the relative humidity is high in cold weather. During cold dry weather, I rarely hear a defrost cycle but during damp wet snow events I hear it defrosting far more often. There are optional baffle structures that are available on some models to keep snow from blowing on the coils but they do nothing for damp air on supercooled surface. Given the Northwest reputation of a wetter climate, I expect the useful low temperature range may be a bit more limited.
I currently have one 12K unit that heats my fairly tight 2 story house down to about 30 degrees. I plan to replace an older mini split AC unit with heat pump version on my second floor office and use that to heat the office rather than heating the entire house.
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