# Woodstove backups, Heat Pumps?



## McKeznak (Jan 8, 2014)

K so I've been watching the forums and everyone is always talking about their heat pumps. To be honest until joining these forums I've never even heard the term used. There's a few Geo-thermal systems around but they are pretty costly and really only found in new builds with a lot of space. I can't imagine you're all talking about those.

So I did what any one would and Google'd them. So if I understand this right is it basically just a reverse A/C unit, sometimes just an A/C in reverse, that instead pushes the warm by-product of the compression into the house instead of expelling it outside?

So whats the deal with them, seems like it's just another way to use electricity to produce heat? Can you get more heat per kWh out of a heat pump than a traditional resister based electric heater?

Anyone know why nobody around here would have one?

_Sorry if it's in the wrong subsection, just always mentioned as a backup to stoves._


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## lopiliberty (Jan 8, 2014)

All I know about them is if I relied on mine for 24/7 heat all winter long I would freeze my a** off.  Theres also a heating element in them that kicks on if its too cold outside and it can't keep up and boy does that make the ol electric meter fly


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## begreen (Jan 8, 2014)

This is more green room topic where there are several threads on heat pumps. There is a huge difference in performance with these units ranging from old inefficient models to modern dual speed compressors or the very popular inverter compressors showing up in mini-split heat pumps.


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## McKeznak (Jan 8, 2014)

Thanks for moving it begreen. Strange yup never really come across these before.


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## begreen (Jan 8, 2014)

You are correct. The best heat pumps are much more efficient than resistance heating.


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## DougA (Jan 8, 2014)

Since you are in NE ON, you may find a heat pump to be a totally worthless proposition. They are great in moderately cold climates but at a certain temperature, the amount of heat they produce is equal to the cost of power they consume and even in S. ON, all the ones I am familiar with have an electric furnace as a backup. That means $$$$$$. Might as well use baseboards as your backup and save the cost of the furnace and duct work.

Ground source is much more efficient because the ground water will be in the mid 50's (here at least) all year long and you can pull a lot of heat out at that temp. The problem is the HUGE cost of installation unless you are on a lake.

When I built my house 30 yrs. ago, I looked into all the options and at that time, heat pumps netted out at zero. By the time you had paid the high up front cost through electricity savings, the unit would be about ready to be replaced from mechanical failure.  They have come a long way since then but I still much prefer passive solar heat on sunny days through my large windows and wood heat. Both of these are very comforting ways to heat.


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## jdp1152 (Jan 8, 2014)

Are we talking about a heat pump or a ground source heat pump here (geothermal)???  Two might different beasts with regard to efficiency.


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## Circus (Jan 9, 2014)

McKeznak said:


> I understand it basically just a reverse A/C unit that pushes the warm by-product into the house instead of expelling it outside?


 
Yes



McKeznak said:


> Can you get more heat per kWh out of a heat pump than a traditional resister based electric heater?


 
If it's not to cold.



McKeznak said:


> Anyone know why nobody around here would have one?


 
It's to cold for air source. Will work in temperate months. I never understood why those throat choking boilers around here were fired up when it's 45 or 50 degrees out side.


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## woodgeek (Jan 9, 2014)

The ratio of how much heat a Heat Pump delivers compared to a resistance heater is called the coefficient of performance, or COP.  the best ductless air source heat pumps, called minisplits get a COP of 3.5-4 during mild weather (>40°F outdoors) and more like 2.5 when it really cold (say 20-25°F).  Below 0°F, COP might be more like 1.5, barely better than a resistance heater.  For a recently made system that looks more like a central AC system, with ducts, called a 'conventional split' (because there is an outdoor and indoor unit connected by refrigerant lines) the COP might be 0.5 less than the numbers above.

Bottom line, in much of the lower 48 and coastal/maritime provinces of Canada, minisplits deliver BTUs on an average seasonal basis that cost about half that of heating oil or propane.  When average winter temps are well below about 20°F, the economic case for them gets a lot worse, and you don't see them as much.  Even there a mini would work great during the shoulder seasons, but the economic case for buying one might still be weaker.


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## peakbagger (Jan 9, 2014)

I have been using a mini split as supplemental winter heating. It seem to be worth running above 10 degrees F. It still puts out some heat above 0 and is rated to down to -15 deg F but the heat output is limited and the efficiency is approaching an electric heater. The minisplit I use is optimized for winter heating. Most standard mini splits will not run much below 50 degrees F. Many large whole house heat pumps also turn on auxiliary electric heaters below 40 degrees so they also become electric heaters when cold. I installed additional solar panels on my home to offset the usage of my mini split on a year round basis but I have access to net metering which allows me to build up a summer surplus of power and use it in the winter. Thus my power costs to run the unit are just the capital cost of the additional panels.

Even a winter optimized mini split heat pump is not going to be backup to a woodstove and if you factor in a loss of power event they are useless. They can be a good supplemental unit for most of the winter thus reducing your wood usage and if your home needs AC during the summer they tend to be far more efficient than window mounted AC units or central heat pump systems that have ducts that run outside of conditioned spaces.


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## McKeznak (Jan 9, 2014)

Brilliant! All of you, thanks!

Ya I was wondering if there were efficiency issues below a certain temperature. Looks like it'll still be Oil backup for me.


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## sloeffle (Jan 9, 2014)

woodgeek nailed the explanation.

I live in Central Ohio and a lot of folks will use their air source heat pump down to 32F and then burn propane or NG below that. Our electric company actually gives you money back if you install a ground source heat pump or an air-air heat pump. I installed a GSHP a few years ago and the cost was actually about the same as an air-air heat pump after the government and utility rebates. The GSHP also makes free hot water in the summer time.


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## Highbeam (Jan 9, 2014)

In my climate we use heat pumps almost entirely for heat. It's just a side benefit that you also get AC. The energy delivered to the space from a heat pump is much more than just the heat of compression. The systems steals heat from the outside air and brings it inside for the home. When it is really really cold outside there is just not much heat to be stolen but the new minisplits are much much better at this than the conventional heat pumps.

If all you know about heat pumps is based on what you see in current houses and on your research from more than 10 years ago then you likely have no idea how good heat pumps have become.


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## McKeznak (Jan 9, 2014)

highbeam is yours one of the more efficient ones? What's the lowest useful outdoor temperature on it?


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## Highbeam (Jan 9, 2014)

McKeznak said:


> highbeam is yours one of the more efficient ones? What's the lowest useful outdoor temperature on it?


 
I grew up with heat pumps and my current house doesn't have one yet. I have chosen to install one of the low temp minisplits from Mitsubishi or FUjitsu that make their full rated output down to 5 degrees F. Below that temp they keep making heat, but at a lower and lower output and COP until they shutoff in the negative teens F. I don't believe that there is ever a point where the heat pumps actually make less heat per watt than regular resistance heat.

In my climate, single digit temperatures happen but the more typical low low is in the teens where the COP of the heat pumps are quite good.

I would not want to buy a traditional and relatively inefficient heat pump and waste all that energy plus have to use electric resistance heat at temps below freezing. That's silly.

The modern minisplits are perfectly capable of heating a house all winter in most inhabited places. Heck, anywhere where the temps are above zero F.


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## velvetfoot (Jan 9, 2014)

But even if working, the mini split would be putting out less and less heat as the temp. drops, meanwhile the heat loss through the bldg envelope gets larger.


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## Highbeam (Jan 9, 2014)

velvetfoot said:


> But even if working, the mini split would be putting out less and less heat as the temp. drops, meanwhile the heat loss through the bldg envelope gets larger.


 
Not until you get below 5 degrees above zero F. the good ones put out full rated output until 5 and then starts tapering gradually. If you get below 5 and must depend on heat pumps then you need to oversize the system to make sure have enough horsepower to keep up with the heating demand.

Old fashioned heat pumps, conventional units, were less able to extract heat from the air at such low temperatures. Those guys needed auxilliary heat sources (electric strip or gas) to maintain output.


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## McKeznak (Jan 9, 2014)

Awesome points thanks guys.

0 F or below is quite the norm here (late dec- mid feb) at least through the nights, so I'm guessing that explains the lack of them. The tech of how they work fascinates me.


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## Highbeam (Jan 10, 2014)

McKeznak said:


> Awesome points thanks guys.
> 
> 0 F or below is quite the norm here (late dec- mid feb) at least through the nights, so I'm guessing that explains the lack of them. The tech of how they work fascinates me.


 
It's also a regional thing. These things are the only way to provide central cooling so you'll see them more in cooling climates where it is so hot and humid that people think that they NEED cooling.

The minisplits are new to the US compared to conventional split systems. The rest of the world is ahead of us on them.


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## jdp1152 (Jan 10, 2014)

McKeznak said:


> Awesome points thanks guys.
> 
> 0 F or below is quite the norm here (late dec- mid feb) at least through the nights, so I'm guessing that explains the lack of them. The tech of how they work fascinates me.



Ground source heat pumps will tackle that without issue.  I barely used any wood last year to test out the system and my overall energy bill for the year was 4k less than the prior year.  I can't attribute all of that to the conversion since I've replaced insulation in wall bays where it was damaged, air sealed the heck out of my house, and had my attics spray foamed.


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## sesmith (Jan 13, 2014)

McKeznak said:


> There's a few Geo-thermal systems around but they are pretty costly and really only found in new builds with a lot of space. I can't imagine you're all talking about those.
> _._



Ground source heat pumps (geothermal) make a lot of sense where you live.  They also make sense as a replacement system in an older house, not just new construction.  You have to look at the big picture, not just the installation cost.  If you're going to be in your house a while, and your alternative is oil heat, it's almost sure to be cost effective to make the switch.

This is our third heating season with our geo system.  No regrets.  It will pay back the installation costs in less than 7 years total.  It keeps the house within a degree of the thermostat set point,works well down below zero, does about 60% of our water heating, serves as a whole house hepa air filter, and gives us central air when we need it in the summer.  It's a very efficient way to heat.  I couldn't buy firewood for what the geo system costs us to run.  Our system replaced a forced air oil furnace in an 1840's vintage house.  I also still have a wood stove but don't use it any more.


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## velvetfoot (Jan 13, 2014)

You'd also have to have ductwork rather than radiators/convectors, another cost if you don't have it.


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## jdp1152 (Jan 13, 2014)

sesmith said:


> Ground source heat pumps (geothermal) make a lot of sense where you live.  They also make sense as a replacement system in an older house, not just new construction.  You have to look at the big picture, not just the installation cost.  If you're going to be in your house a while, and your alternative is oil heat, it's almost sure to be cost effective to make the switch.
> 
> This is our third heating season with our geo system.  No regrets.  It will pay back the installation costs in less than 7 years total.  It keeps the house within a degree of the thermostat set point,works well down below zero, does about 60% of our water heating, serves as a whole house hepa air filter, and gives us central air when we need it in the summer.  It's a very efficient way to heat.  I couldn't buy firewood for what the geo system costs us to run for heat.


 
Like wise.  I still like to cook myself out of a room with wood I cut mysel though


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## jdp1152 (Jan 13, 2014)

velvetfoot said:


> You'd also have to have ductowrk rather than radiators/convectors, another cost if you don't have it.


 
Ductwork is surprisingly cheap.  For my install it accounted for 2k in materials. No clue on labor as it was only one line item on the invoice.


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## velvetfoot (Jan 13, 2014)

Alas, I have a two story house.


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## jdp1152 (Jan 14, 2014)

velvetfoot said:


> Alas, I have a two story house.



I have a two story as well, but had two systems installed.  One in my upstairs attic and one in my unfinished basement.  There was existing duct work in the attic from the AC that I had, though we had it replaced since the cost wasn't high.


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## begreen (Jan 18, 2014)

I have a 2 story old farm house too. Instead of trying to duct heat to all 4 rooms upstairs I ran only 2 ducts. One up the wall cavity to the hallway and one up in corner of a bathroom closet to the master bedroom. This has worked out pretty well. The other bedrooms and bathroom get enough heat via convection from the large open staircase. The heat pump covers us to around 24F and then switches to resistance electric. But when it is that cold (not too often) we have the wood stove carrying the load 24/7.


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## velvetfoot (Jan 18, 2014)

That way stuff is not in the attic, which is good.


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## begreen (Jan 18, 2014)

Ya, no A/C needed here. We are naturally air-conditioned by Puget Sound.


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## jdp1152 (Jan 18, 2014)

velvetfoot said:


> That way stuff is not in the attic, which is good.



My attics a spray foamed so no big deal to have ducts and equipment up there.


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## Highbeam (Jan 19, 2014)

begreen said:


> I have a 2 story old farm house too. Instead of trying to duct heat to all 4 rooms upstairs I ran only 2 ducts. One up the wall cavity to the hallway and one up in corner of a bathroom closet to the master bedroom. This has worked out pretty well. The other bedrooms and bathroom get enough heat via convection from the large open staircase. The heat pump covers us to around 24F and then switches to resistance electric. But when it is that cold (not too often) we have the wood stove carrying the load 24/7.



Unfortunately for us Puget sounders, when it gets down into the 20s we are often banned from burning due to air pollution.


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## begreen (Jan 19, 2014)

Yes, Pierce County in particular is an inversion pocket. Mt. Rainier is a heckuva big backstop.


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## DougA (Jan 20, 2014)

Geothermal is great under many conditions but not all. As stated, if you are retrofitting a house without ductwork it can be a big problem in cost and in the ability to get ducts where they need to go at all. I did install ductwork in my home after the fact and it was much higher than a few grand. The cost of well drilling is variable, depending upon what is in the earth under you. Drilling through solid rock can be prohibitively expensive compared to sand and gravel. Also, geothermal works best (pretty well mandatory) to have a great deal of ground water to move temparate water onto your underground pipes. Not all areas have enough water within a reasonable distance to the surface, although it can easily work with sour water as easily as sweet water, since you are using the energy, not the water itself.
The cheapest way to do it is if you have a large pond on your property. They can run the piping at the bottom of your pond and you eliminate the huge expense of drilling. I've got a 12 acre swamp right beside me but it is a restricted wetland zone.  Never fool with environmentalists who work for the gov't.


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## georgepds (Jan 23, 2014)

DougA said:


> Geothermal is great under many conditions but not all. ....



There is a good discussion on the relative merits of air vs ground heat pumps  at green building advisors:

http://www.greenbuildingadvisor.com/blogs/dept/qa-spotlight/air-source-or-ground-source-heat-pump

and here 

http://www.greenbuildingadvisor.com...e-affordable-ground-source-heat-pumps-horizon


The new ASHP are as efficient as the GSHP under many conditions ( often the GSHP number do not factor in the energy to pump and circulate the water because " the new ISO standard eliminated all pumping energy from COP calculations" ) , and a lot less costly ( you don't have to drill a well for the heat exchanger)


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## sloeffle (Jan 23, 2014)

My GSHP was around the same cost ( plus or minus 1k ) as if I were to have installed an ASHP with a propane furnace after the 30% rebate. The problem that I have with a lot of these articles is that they do not take the cost of cooling into affect. They only talk about heating. A GSHP is a lot cheaper to cool with than ASHP.

My GHSP cools 2100 sqft for less money that it took a 10 SEER AC unit to cool 1400sqft. While the AC is running I am also making free hot water.


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## georgepds (Jan 23, 2014)

sloeffle said:


> ....
> 
> My GHSP cools 2100 sqft for less money that it took a 10 SEER AC unit to cool 1400sqft. While the AC is running I am also making free hot water....



Do you have a SEER for your GSHP?

FWIIW, my 12krls2 Fujitsu mini-split ASHP has a SEER of 25 (the 9000 btu/hr go to 27) . The new ASHPs with the variable speed DC condensors are very efficient .The higher the number the better the uinit

The Fujitsu site shows the SEER dropping from 27 to 21 as the unit size increases from 9k  to 14.5 k BTU/hr. You can install multiple small units to keep both the SEER and capacity high   

http://www.fujitsugeneral.com/wallmountedRLS2_specs.htm

There are 3 numbers to use when evaluating a heat pump that can cool ( SEER) and heat (HSPF)  and both (EER).


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## razerface (Jan 23, 2014)

DougA said:


> .
> The cheapest way to do it is if you have a large pond on your property. They can run the piping at the bottom of your pond and you eliminate the huge expense of drilling.


that may be cheapest in the short term. It also means there is limited things you can do to the pond after the geo is installed in it. No machinery in the pond, no digging, ect. The pond must be able to maintain the temp needed also (read deep enough)

The best we found is trenches with loops installed. I do not like the idea of wasting so much water to heat and cool with as in drilling a well for it. The ground trenches require nothing once installed and do not restrict the use of the ground above the loops.


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## Dave A. (Jan 23, 2014)

Still not clear at what BTU point these mini splits go from requiring 240v vs. 120v.  Or if it varies by mfr.   (1st had assumed that they were all requiring 240v, then noticed some 1 ton (12000 BTU) units were only 120v.  (it's an issue for me since the main box is close to being tapped out).


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## georgepds (Jan 23, 2014)

Dave A. said:


> Still not clear at what BTU point these mini splits go from requiring 240v vs. 120v.  Or if it varies by mfr.   (1st had assumed that they were all requiring 240v, then noticed some 1 ton (12000 BTU) units were only 120v.  (it's an issue for me since the main box is close to being tapped out).




Probably varies by manufacturer.. even the 3/4 ton fujitsu (9 k btu/hr) units require 240 v


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## sloeffle (Jan 23, 2014)

georgepds said:


> Do you have a SEER for your GSHP?.



According to the Waterfurnace web site the EER is 30 and the COP is 4.8.

http://www.waterfurnace.com/products.aspx?prd=500A11

The green building article does make some good points about finding the correct installer. They all do it their own way and you need to wade through the BS to find the correct person. One installer wanted to put 600' of pipe in the ground. My current system has 2400'. 

I guess the point I am trying to make is that the *informed consumer* needs to pick the best solution for their problem. In my situation I would need probably 5 mini splits on my house due to the layout. It is a ranch with lots of small rooms. IMHO this does not make sense even if they give me the most bang for my dollar. If I lived in a house with a open floor plan then it probably makes more sense.

I was against getting GSHP at first due to the up front cost. Then I started comparing numbers and it won. But if I had to drill wells or dig a pond an ASHP with propane backup would of won.


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## BEConklin (Jan 24, 2014)

We had an LG mini split AC/Heat Pump system (LMU369HV) installed this past November. It's rated at a heating capacity of 41,000 BTU @ 47° F but that drops down to 26,000 BTU @ 17°F. There are three, 12,000 btu heads for it, two in the main living area on the main floor, and one in the finished portion of our basement, where my office is located. So far, it's done a great job of providing the only heat in the basement (other than the heat that comes off the oil burner itself), as well as providing much of the heat we need on the main floor and in the two bedrooms situated in a loft above the living/dining room.  I really like the system - it heats the whole space evenly and it's whisper quiet. Even the outdoor unit is pretty quiet - you can't hear it at all from anywhere inside the house unless you open the doors or windows. I'm sitting about 20 feet away from the outside unit right now - it's on the other side of the concrete foundation wall - at about eye level with me sitting down - and I can't hear it. 
We do use the oil burner when the temp gets down into the twenties and below - first: because the overall efficiency for the mini split system falls off and second: because I don't want the pipes from the oil burner to the upstairs radiators freezing overnight - they're enclosed in the exterior wall on the north side of the house. 
I'm sure it will take some time to recoup the cost of having this system installed, but so far it's saved us quite a bit - I'd say we're at about half of what we spent to heat the house with oil last winter at this same point - and back then we hadn't even moved in then so we had the temp set at 62°. 
I can't wait to see how well it cools the house come summertime - last summer we had moved in - and it was wicked hot and humid in the house. One morning I went to take a shower and there actually were mushrooms growing from a gap in the vinyl floor in the downstairs bathroom.  We can't install window AC units because all the windows are crank out casements - we really suffered.


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## Laszlo (Apr 30, 2014)

DougA said:


> The cheapest way to do it is if you have a large pond on your property. They can run the piping at the bottom of your pond and you eliminate the huge expense of drilling.


What about a covered-over swimming pool? Ours hasn't seen much use in the last decade--took too much effort to keep clean and repaint. Now that it needs a new filter pump and the waterline tiling redone, I was thinking it might be better to fill it in anyway. But it's retained water well for all these years, and is situated close to our current water heater and ASHP. I have a feeling a 9-ft (on the deep end) residential pool wouldn't cover the needs of a 2,400 sq. ft house, but it might cut down on the trenching enough to make geothermal worthwhile.


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## begreen (May 1, 2014)

We've had our American Standard central heatpump system for 8 years now.  It has a very high efficiency dual-stage compressor and a dc-motor variable speed air handler. The system works well from about 23F on up. It has a large electrical coil system in it for backup but we've only used that once when returning from vacation in the winter and I wanted to warm the house up from 55F quickly. The heatpump is used exclusively when outdoor temps get above 45-50F. It is always on and sometimes comes on if I am slow on reloading the stove. The cost of running the unit is small, almost laughably so as compared to when we were heating with propane and wood.


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## Highbeam (May 2, 2014)

begreen said:


> We've had our American Standard central heatpump system for 8 years now.  It has a very high efficiency dual-stage compressor and a dc-motor variable speed air handler. The system works well from about 23F on up. It has a large electrical coil system in it for backup but we've only used that once when returning from vacation in the winter and I wanted to warm the house up from 55F quickly. The heatpump is used exclusively when outdoor temps get above 45-50F. It is always on and sometimes comes on if I am slow on reloading the stove. The cost of running the unit is small, almost laughably so as compared to when we were heating with propane and wood.


 
Our power is cheap, under 10 cents per kwh, and our climate is mild. We in the PNW are prime candidates for heat pump heating. I just have had too many friends, relatives, and coworkers need to replace their heat pump systems with 5-7 years of use at a cost of nearly 10k$ for the replacement. If they were more dependable and/or cheaper I would expect to see more of them.


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## begreen (May 2, 2014)

I guess we and many of the folks locally are just beating the numbers then. A good heat pump is as reliable as a good refrigerator. When and if a compressor fails one should replace it, not the entire system. Also, many smaller homes get away with one or two mini-splits for a total installed cost closer to $5K locally.


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## woodgeek (May 2, 2014)

There are a lot of bad HVAC techs out there, as well as ones that will sabotage existing systems when business gets slow to get the replacement business.  Stats have shown that folks that get annual 'checkups' on their heat pumps get a shorter equipment service life than those that don't. 

They are essentially zero maintenance units (unlike oil burners that are now up to >$200/year), change the air filters regularly, and keep the outdoor unit clear of leaves and debris...done.  I'm at 8 years and counting with a 'cheapo' 'builder-grade' 4-ton Goodman.  I budgeted 10 years for my ROI calcs, might get 15, who knows? I'm running it hard...>2000 hours of compressor runtime per year.

Have a buddy who just had his gas furnace and AC 'check-up'.  He leaves the tech alone while he is working, there is an enormous 'clang' noise, and he runs back. The tech says "Your heat exchanger is cracked, you need to buy a new furnace, or replace the exchanger [for 70% of the price of a new furnace]"!!  What do you think that noise was?


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## mellow (May 2, 2014)

Good to see I am not the only one running Goodman units,  mine have held good so far for the past 5 years.  I have have two 1 ton units, one in crawlspace and one in the attic each heating/cooling 600 sq feet, well the upstairs gets run more in the winter as the wood insert is only good upstairs till we get into the lower 30's with no wind (no insulation in my walls).

I was actually thinking about having the tech come by and service it but I think I will hold off, it is running good.


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## peakbagger (May 3, 2014)

I used to pay Honeywell building services to maintain industrial AC equipment. We paid for uptime not for service so they only did the service that was needed to keep the equipment running reliably. On air cooled units they replaced the filters and checked the belts. On an infrequent basis they checked the temps out. That was about it. On water cooled units, they acid cleaned the coils yearly and changed the filters. These units were in nasty conditions (paper and pulpmill with corrosive atmosphere). 

One big caveat is to make sure that the power feed to the unit is good. Run adequate sized conductors so that there isn't voltage drops.


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## mellow (Oct 22, 2014)

Well, my streak came to an end on Mondays cold snap.  Turned on the downstairs Goodman heat pump Sunday night for the first time this year and came down Monday morning to find the emergency heat was stuck on and the downstairs was 76 degrees, only way to get it to shut off was flipping the breaker.  Called my friend who installed it and it turns out the heat sequencer went up and also took out my blower control, looking at $200 max in parts and labor.  Apparently this is a common issue for Goodman units.

Just an FYI, if you ever find you can't shut the system off via the thermostat and the Emergency heat is stuck on more than likely it is the sequencer, the blower will always run if the emergency heat is on so it won't melt down the heat coils.


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## Lumber-Jack (Oct 22, 2014)

We installed an air source heat pump when we bought and renovated the house we are living in, problem is we also installed the wood stove at the same time, so I have yet to really put our heat pump to the test in the cold of winter since we pretty much heat exclusively with wood. In the meantime the heat pump functions as an awesome central air conditioning system in the summer time when we think that we "NEED" cooling.


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## begreen (Oct 22, 2014)

I feel almost embarrassed that we have a heat pump but never use it for cooling. Well, almost never. I did turn it on a couple years ago one hot summer day to cool down my wife.


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## mellow (Oct 22, 2014)

Wish I had that problem begreen. Summer is when mine get used the most, if they had an emergency cooling option I am sure my wife would have that running some of those 100 degree days.


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## Highbeam (Oct 22, 2014)

begreen said:


> I feel almost embarrassed that we have a heat pump but never use it for cooling. Well, almost never. I did turn it on a couple years ago one hot summer day to cool down my wife.


 
This winter has been great for heat pumpers so far. So warm, it was just under 60 degrees last night. Hard time of year to heat with wood since only a little bit of heat is needed.


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## begreen (Oct 22, 2014)

Yes, this may be the longest year we've gone without a fire.


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## moey (Oct 22, 2014)

DougA said:


> The cheapest way to do it is if you have a large pond on your property. They can run the piping at the bottom of your pond and you eliminate the huge expense of drilling. I've got a 12 acre swamp right beside me but it is a restricted wetland zone.  Never fool with environmentalists who work for the gov't.



Most folks I had come out and quote preferred digging trenches as being the least expensive. Ponds require a lot of labor for installation. Ever try and get a HDPE pipe to sink? They do have a little bit better performance in most cases though the water conducts much much better then dirt and stays warmer often.


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## DBoon (Oct 22, 2014)

I was really soured on "heat pumps" for many years after having one in a condo.  It seemed to mostly blow cold air, cost a lot to run, and the backup heat was on a lot. 

I installed a Fujitsu RLS2H (15,000 BTU rated, usable heat down to -17 degrees F) in an ~1800 square foot (unoccupied) home that I am renovating. It uses electricity from my 5.3 kW solar array.  Last year was the coldest winter in a long time in Central NY - consistently below 0 degrees F, 8000 heating degree days, and that little unit saved me about 400 gallons of heating oil using about 4 MWh of electricity.  It produced very nice heat down that I could feel when outside temps were below zero.   Would I rely on this for my primary heat in my climate?  No, but it is a good backup system, great for shoulder season, and certainly a very reasonable "keep the house at 60 degrees F while away" heater if you primary heat was from a wood stove.  

If you go this route, make sure you get the Fujitsu or Mitsubishi units that are rated to -17 degrees F.


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