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Helpful? 2

Are Affordable Ground-Source Heat Pumps On the Horizon?

Perhaps, but there’s only one problem: as we approach the horizon, the horizon keeps receding

Posted on Apr 5 2013 by Martin Holladay, GBA Advisor

My grandfather, William L. Holladay, was a refrigeration and cooling engineer. Decades ago, he wrote a pioneering, speculative article on ground-source heat pumps, “The Heat Pump: What it does, and what it may do someday.” The article appeared in the October 1948 issue of Engineering and Science Monthly. (For a basic explanation of how a heat pump works, and the difference between an air-source heat pumpHeat pump that relies on outside air as the heat source and heat sink; not as effective in cold climates as ground-source heat pumps. and a ground-source heat pump, see Heat Pumps.)

Even back in 1948, my grandfather realized that the Achilles’ heel of ground-source heat pumps was their high cost. He wrote, “To use earth heat, a hole must be dug, and the cost, while not always predictable, will surely be high: maybe from 25 to 50 per cent of the entire project.”

In the six decades since my grandfather’s article was published, engineers have not given up on ground-source heat pumps (GSHPs). Among those who remain enthusiastic about these systems are a group of true believers who are convinced that (a) this is a wonderful technology, and (b) there must be a way to bring costs down.

Ground-source heat pumps are still expensive. One fan of the technology, Brian Clark Howard, has provided the following guideline to system costs: “In our book Geothermal HVAC(Heating, ventilation, and air conditioning). Collectively, the mechanical systems that heat, ventilate, and cool a building., my co-author, Jay Egg, crunches the numbers for a typical homeowner, based on his 20+ years in the business. For a home geothermal system, he estimates the total installed cost at $42,000.”

This estimate is similar to those made by two installers of ground-source heat pumps from Maine, Jeff Gagnon and Jim Godbout. In an episode of the Green Architects’ Lounge series on the GBA website, Gagnon estimated the cost of a residential GSHP system (including the cost of a drilled well) at $30,000 to $42,000, while Godbout gave an estimate of $40,000 to $50,000.

Blame the backhoe operators and well drillers?

Back in 1995, Steve Kavanaugh, a professor of mechanical engineering at the University of Alabama and a nationally known expert on GSHPs, wrote a paper called “Cost Containment for Ground-Source Heat Pumps”. In that paper, Kavanaugh noted, “High installation costs have been identified as a major barrier to wider application of ground-source heat pumps (GSHPs), often referred to as geothermal heat pumps. The primary reason cited for higher cost is the ground loop.”

After looking into ground loop costs, however, Kavanaugh disagreed with industry experts who blamed backhoe operators and well drillers for the high cost of GSHPs. Kavanaugh wrote, “This study indicates the labor, overhead, and profit in horizontal loop installation [are] actually lower than the prevailing cost of equivalent activities in the construction industry.”

Since 1995, the cost of GSHP systems has gone up sharply. When Kavanaugh recently analyzed the reasons for the skyrocketing costs, he again found that the main culprit for high system costs is not the cost of the ground loop; it’s the high cost of the equipment installed in customers’ basements.

Equipment costs are rising faster than ground loop costs

In a 2011 study, Kavanaugh analyzed the cost data for of forty GSHP systems. The results of his research were published in the October 2012 issues of ASHRAEAmerican Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). International organization dedicated to the advancement of heating, ventilation, air conditioning, and refrigeration through research, standards writing, publishing, and continuing education. Membership is open to anyone in the HVAC&R field; the organization has about 50,000 members. Journal, in an article titled “Long-Term Commercial GSHP Performance.”

Kavanaugh and his fellow researchers concluded that, since his original 1995 survey of GSHP systems, the cost of the HVAC components for GSHP systems has increased by 177%, while ground loop costs have only increased by 52%. Kavanaugh wrote, “The percentage of ground loop costs to total GSHP system cost have declined from 38.5% in 1995 … to 25.5% in 2011. …Thus, attempts to optimize GSHP cost by focusing primarily on the ground loop seemed illogical.”

Kavanaugh was recently interviewed by Energy Design Update, a monthly newsletter. In that February 2013 interview, Kavanaugh said, “My conclusion — which is the opposite of the industry, as the industry is calling for the cost of the loop to come down — is that, considering inflation, the cost of the loop has come down in areas with mature, competitive markets, and can’t go much further. Equipment costs, meanwhile are going through the ceiling.”

Inflated efficiency claims

Kavanaugh has long been concerned about the exaggerated energy efficiency claims made by GSHP manufacturers. When I first interviewed Kavanaugh on the topic back in 2007, he decried competing efficiency claims by GSHP manufacturers and air-source heat pump manufacturers as “a lying contest.”

Five years later, Kavanaugh’s opinions on the issue haven’t changed. In the February 2013 EDU interview, Kavanaugh said, “I believe that the GSHP industry has created a deceptive rating system to counter the deceptive air-source heat pump rating system. I feel it really hurts the industry, as it promises unrealistic energy efficiency numbers when, in fact, they are less efficient units that what the ratings suggest.”

The problem dates back to 2000. On January 1, 2000, a new standard (ISO standard 13256-1) replaced two earlier standards (ARI 325 and ARI 330) used to rate the efficiency of GSHPs. Whereas the ARI standards included an allowance for the electricity used by pumps to draw well water or circulate fluid through ground loops, the new ISO standard eliminated all pumping energy from COPEnergy-efficiency measurement of heating, cooling, and refrigeration appliances. COP is the ratio of useful energy output (heating or cooling) to the amount of energy put in, e.g., a heat pump with a COP of 10 puts out 10 times more energy than it uses. A higher COP indicates a more efficient device . COP is equal to the energy efficiency ratio (EER) divided by 3.415. calculations. The effect was that COP ratings jumped up: for the same piece of equipment, the COP rating under the new ISO standard was higher than the COP rating under the old ARI standards.

For consumers, the advantage of the old ARI method was that it at least made a stab at including pump and fan energy — unlike the current ISO method, which simply abandons any attempt to account for these essential energy inputs.

Dan Ellis is the president of ClimateMaster, a GSHP manufacturer. Back in 2007, Ellis defended the new ISO standard. “The rating should be used to compare one box to another,” Ellis told me. “In the residential market, no one is going straight from the rating and saying, ‘That is what you will get in your real house.’”

In spite of Ellis’s assertion, however, GSHP manufacturers often blur the line between unit COP and system COP. For example, this is how another GSHP manufacturer, WaterFurnace, boasts about a heat pump with a COP of 5: “A WaterFurnace geothermal system … can deliver an astounding five units of energy for every one unit of electrical energy used.” Since this calculation ignores pump and fan energy, the statement is false.

In the February 2013 EDU interview, Kavanaugh said, “To calculate performance on these multi- and variable-capacity models, the standard [ISO Standard 13256-1] calls for water temperature in the loop to be 68°F, which is ridiculous, because loops operate at much higher temperatures in cooling. Essentially, what you have there is a something similar to rating the efficiency of a car or truck … when it’s rolling down the hill. If the evaporator coil is 80.6°F and the water coil (condenser) is 68°F, you can get a ridiculously high efficiency reading. On top of that, these calculations assume that the fan has no static pressure. … When you take that piece out of the rating, you get a very deceptive, high efficiency rating.”

[Author's postscript: Tony Cooper, a distributor of GSHP equipment in Frisco, Texas, posted a blog in response to this article. Cooper asserts that any discussion of inflated efficiency claims "is absolutely irrelevant" because "homeowners don't know or care what SEER(SEER) The efficiency of central air conditioners is rated by the Seasonal Energy Efficiency Ratio. The higher the SEER rating of a unit, the more energy efficient it is. The SEER rating is Btu of cooling output during a typical hot season divided by the total electric energy in watt-hours to run the unit. For residential air conditioners, the federal minimum is 13 SEER. For an Energy Star unit, 14 SEER. Manufacturers sell 18-20 SEER units, but they are expensive. , EER, or COP mean."]

Most rating methods are flawed

Of course, all efficiency rating systems are subject to criticism: for example, the AFUEAnnual Fuel Utilization Efficiency. Widely-used measure of the fuel efficiency of a heating system that accounts for start-up, cool-down, and other operating losses that occur during real-life operation. AFUE is always lower than combustion efficiency. Furnaces sold in the United States must have a minimum AFUE of 78%. High ratings indicate more efficient equipment. of gas furnaces ignores electricity use, while SEER ratings overstate the performance of air conditioners during humid weather. Similarly, the heating season performance factor (HSPF) does not accurately predict the installed performance of air-source heat-pumps.

Kavanaugh notes, “In defense of water-source heat pump manufacturers’ desire to use this deceptive rating system, it is important to understand the system used by competing air-source heat pumps. In cooling, the SEER, if it’s a single-speed machine, will be determined when the inside air temperature is at 80°F and the outside air is 82°F. With these conditions, you honestly might as well open your windows. … Equipment manufacturers are playing games, getting really high COP and SEER, which all are really inflated. … Owners have to be really careful when someone quotes them COP or EER. Ratings have huge gaps in them, and don’t include pump operation, either. Some designers and installers do sloppy work and end up putting huge pumps on to compensate for poor piping plans. The big pumps take a huge chunk out of potential efficiency.”

Equipment vendors always want to sell more equipment

The aims of manufacturers and vendors of ground-source heat pumps may differ from the aims of a builder or homeowner. “Ground-source heat pump manufacturers often sell pump kits with two pumps when only one pump is needed,” Kavanaugh told me when I interviewed him recently. “For example, consider the use of 3/4-inch U-tubes [for vertical ground loops] for a 4-ton heat pump with which manufacturers typically provide a kit with two pumps. What you need is 1-inch U-tubes and upsized headers from the size (1-1/4 inch) that the GHP vendors often recommend to one that provides less head loss (1-1/2 inch). Then you only need one pump. This will result in an 8 to 10% higher system efficiency and the savings on the pump will more than offset the cost of the larger U-tubes and headers. But the vendors prefer to sell two pumps, because manufacturers always like to sell more equipment. Installers tend to buy into the vendors’ recommendations about the size of the ground loop. These loops are typically smaller and shorter than they should be. It’s important that the ground loop be correctly sized. But when costs become too high for the client, some manufacturers and vendors would rather see a larger fraction of the money go to equipment and a smaller fraction to the ground loop — because they aren’t making any money on the ground loop.”

Clearly, it doesn’t make much sense for a contractor designing a ground loop to rely on advice from an equipment vendor. Instead, Kavanaugh advises system designers to use LoopLink software from GeoConnections, Inc.

Why is there such a dearth of field data?

Many residential energy experts — including Marc Rosenbaum, Andy Shapiro, and Henry Gifford — have bemoaned the lack of performance data on installed residential GSHP systems. When I spoke to Kavanaugh recently, he acknowledged the problem. “What is needed is field data (and a lot of it) to verify installation quality and what actually works well,” he said. “The Department of Energy seems more interested in pie-in-the-sky type of equipment with a low probability of being affordable rather than measured field data. So that is a major source of funding that is not available. We tried to get a research project funded through ASHRAE to gather field data on commercial building ground-source heat pump performance, and it was rejected three times. But I guess they felt it wasn’t research-y enough. Fortunately we were able to obtain funding through the Electric Power Research Institute, the Tennessee Valley Authority, and the Southern Company. Ironically, the publication arm of ASHRAE was much more interested than the research folks, since results of the project have been published by the ASHRAE Journal. ”

While Kavanaugh’s study of the performance of commercial GSHP installations is certainly useful, no comparable study of residential GSHP systems has yet been made.

Kavanaugh is still loyal to the technology

Kavanaugh is aware that the high cost of GSHP systems puts the technology out of reach for most homeowners. The February 2013 EDU interview quotes him as saying, “The economics in the commercial building sector are much better than those in the residential. I really have some concerns, and am disappointed for the residential sector because heat pump technology is primarily restricted to high-end applications, because of economics. … It is often not a good bargain for the average customer.”

Nevertheless, Kavanaugh remains a fan of the technology. “I can assure you, I would never have an air-based heat pump in my home,” Kavanaugh told me.

Kavanaugh still hopes that the cost of GSHP systems will eventually drop. “It is a product that has a 20% smaller compressor than an air-source heat pump,” Kavanaugh told me. “Compared to a split system, it should have half the sheet metal, half the aluminum, and half the copper in it. It should have less than half the controls in it. If the product were widely used, if it were common, it would cost less than a split-system air conditioner/heat pump. But the current situation is that that device costs more than a split system unit, and it should not. ... If you could install the system inside the building, with the pump and ductwork, for the equivalent of an air-source system, the economics would be better. The only premium would be for the ground loop.”

These systems don't make sense for homes

If you've read this far, you probably realize that the answer to the question posed at the top of the page — are affordable ground-source heat pumps on the horizon? — is no. When it comes to residential heating and cooling loads, the trend is toward smaller loads (due to improved building envelopes with reduced air leakage, thicker insulation, and better windows), not larger loads. A home with a good thermal envelope doesn't need much heating or cooling, and it certainly doesn't need a $42,000 HVAC system.

For that matter, it probably doesn't even need a $28,000 HVAC system. Now that a few ductless minisplit units can heat or cool your home with an average COP of 2.0 or more, residential ground-source heat pumps, like solar thermal systems, just don't make any sense.

Martin Holladay’s previous blog: “Ventilation Rates and Human Health.”

Click here to follow Martin Holladay on Twitter.


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Image Credits:

  1. Andy Shapiro

1.
Fri, 04/05/2013 - 07:23

You tease
by Dan Kolbert

Helpful? 1

Is there any new equipment coming down the pike? I've always figured I need a GSHP like I need a hole in my head, but if there's a reason to reconsider I'd be interested. Jim Godbout & I have had many conversations on the subject - my sense is he doesn't typically recommend them for residential.


2.
Fri, 04/05/2013 - 07:38

Edited Fri, 04/05/2013 - 07:47.

Response to Dan Kolbert
by Martin Holladay, GBA Advisor

Helpful? -1

Dan,
Evidently the irony in my chosen title is a little confusing. I guess it's time for me to add a paragraph or two at the end of the article to warn readers away from GSHPs in residential applications.

I've added a P.S. I've made my conclusions explicit in the new section at the end, "These systems don't make sense for homes."


3.
Fri, 04/05/2013 - 07:50

Utility Room Size
by Daniel Ernst

Helpful? 0

I don't have any direct experience with GSHPs. One thing that always shocks me about these systems is the sheer size of the equipment---and the space requirement for that indoor equipment. Kind of evokes the old basement furnace look. Retro-techno-groovy . . .

I wonder how often the additional square footage costs are included in the calculation?

Heat pump efficiency exaggerations aside, if you are working to reduce square footage and improve efficiency, GSHPs seem like a step in the wrong direction.


4.
Fri, 04/05/2013 - 07:52

It's that dry Yankee wit
by Dan Kolbert

Helpful? 0

Ayuh. But now I get it - ground, horizon, etc. On the internet no one knows you're a dog.


5.
Fri, 04/05/2013 - 08:01

Response to Dan Kolbert
by Martin Holladay, GBA Advisor

Helpful? 0

Dan,
I refuse to draw faces with punctuation marks -- I'm to old to learn text-speak -- so I guess I need to be more careful with my irony.


7.
Fri, 04/05/2013 - 08:42

It's still April
by Dan Kolbert

Helpful? 1

all is forgiven. And Friday the 13th comes on a Saturday this month.


8.
Fri, 04/05/2013 - 08:52

high costs ...
by Jin Kazama

Helpful? 0

i didn't read through it all ..as i was uninterested to learning more after the first 3-4 paragraphs...but i agree with the conclusion that a 40 000$ heating/cooling setup , + hight maintenance , tuning and setup cost is ridiculous for any regular residential building ..

a friend of mine , locally ( near Montreal ) who is a tradesman ( excavation entrepreneur ) built a ~ 1million$ house ( his own ) a few years ago , and installed a ground loop heat pump system for his pretty large ( 100ft long .. ) dwelling. ( ICF + ok windows )
Even though he did the ground work himself, the installed system still costed more than 80 000$
( including the ~ 20 000$ central air + ducts ) , has already required more than 5000$ of maintenance, and still doesn't provide 100% of his heating needs.
Will probably never pay itself when some more maintenance will be required,
it is sooo complex that i couldn't even understand the pump/relay setups in 30mins of looking at it ...
also the fact that ground gets to ~5C during winter here probably doesn't help the efficiency much
for heating purposes ..

again same situation a purchasing a 40-50K$ current range limited EV to save on fuel cost,
where the limited range restricts the application to someone that doesn't work that far from home
hence cannot save enough per year to justify the additional investment over a hybrid or efficient ICE powered vehicle.

wouldn't someone be best to invest 10000$ more on insulation and sealing,
and use mini splits instead of 40 000$ on geo setup ??


9.
Fri, 04/05/2013 - 09:11

Short answer
by Dan Kolbert

Helpful? 0

yes


10.
Fri, 04/05/2013 - 11:56

Edited Fri, 04/05/2013 - 11:57.

2 + 2 ur points...
by Armando Cobo

Helpful? 0

My argument to stay away from GSHPs, in addition to your points, is that if I make the building enclosure really tight and install good insulation, my heating/cooling loads are so small that the GSHP ROI is way too long. ;-))


11.
Fri, 04/05/2013 - 12:51

It comes down to application and choice
by Adam Gloss

Helpful? 0

While I agree that ductless heat pumps can be a much more cost-effective solution then geothermal, application and customer choice will always dictate the right approach. We are a residential retrofit company that offers both geothermal and ductless heat pump systems.

While we do A LOT more ductless jobs, there is a place for geothermal. Too often conversations like this focus on finding THE solution, not recognizing that there is no ONE solution, but LOTS of solutions. If they fit the application well, are energy efficient, provide good comfort and indoor air quality, etc., then why limit consumers choices?

By focusing on what is important to customers, giving them solutions to meet those needs, and providing them with the information they need to make an informed decision, they will usually make the right choice!


12.
Fri, 04/05/2013 - 19:04

No one size to fit all
by Dick Russell

Helpful? 0

Adam has it right, that there is no one solution that is best for all situations. In my case, the house is superinsulated, so that the GSHP is small (2-ton) and runs in just first stage all winter. Also, the house needed a well anyway for domestic water, and the well didn't have to be any deeper than was needed to get adequate water supply for the house. So extra well-related costs were minimal and didn't add substantially to the overall GSHP cost. I wanted summer A/C, and a zoned system, so that part of the total HVAC cost was for that.

It's hard to generalize about total system cost. It would be more useful to talk about incremental costs to go GSHP vs some other solution to the whole HVAC issue for a particular house. Clearly, GSHP isn't overall the best solution for everyone, but it can make sense for some.


13.
Fri, 04/05/2013 - 21:26

Unfortunately, you are both wrong.
by Jin Kazama

Helpful? 0

There is always only 1 solution.
We can only strive to make the best compromises to get as close as possible to the perfect setup.
GSHP is not interesting for any regular well insulated house.
Way too complexe, way too expensive ...

now if you remove the H from GSHP ... now u get something interesting .!
GSP is da man :p

( sorry i'm tired .. )


14.
Fri, 04/05/2013 - 21:29

Dick: what was the cost of ur
by Jin Kazama

Helpful? 0

Dick: what was the cost of ur setup ?

DIY GSHP might be the only one worth it because it brings the costs down quite much,
such as using a nearby water source etc ...


15.
Fri, 04/05/2013 - 23:31

You need a lesson
by Jamie Clark

Helpful? -1

I would double check your sources for this article. My average 3 ton geo runs about $20,000 and after the tax credit the payback for it is only a few years longer than a 2 stage heat pump. I'm teaching a class on geo in Cincinnati in June I'd love to have you, message me and I'll give you a discount. In the mean time please stop spreading bad information about geo.


16.
Sat, 04/06/2013 - 05:13

Response to Adam Gloss and Dick Russell
by Martin Holladay, GBA Advisor

Helpful? 0

Adam and Dick,
I agree that there may be a few residential projects where a GSHP makes sense. These homes would typically be very large.

In most cases I have seen, however, homeowners who have paid for a GSHP system have paid too much for their HVAC equipment and not enough on their thermal envelope (airtightness, insulation, and windows). Time and again, I have reviewed "green" homes with overpriced GSHP systems and underwhelming envelope specs.

I have also interviewed several builders who went through a phase of specifying GSHPs for their projects, and who now say, "never again." They have reached this conclusion because of commissioning problems and maintenance problems with GSHP systems, because of the high price of GSHP systems, and because of the simplicity and affordability of ductless minisplits.


17.
Sat, 04/06/2013 - 05:29

Edited Sat, 04/06/2013 - 05:31.

Response to Jamie Clark
by Martin Holladay, GBA Advisor

Helpful? 0

Jamie,
You wrote, "I would double check your sources for this article." I can assure you that my quotes from GSHP contractors are accurate.

I don't doubt that you (and many other contractors) are sometimes able to install a residential GSHP system for $20,000. Clearly, a $20,000 GSHP system is a better value than a $42,000 GSHP system, all other factors being equal. Even at that price, however, it may not be a good value.

In your comments, you also raise the question of federal tax credits for GSHP systems. The question of incentives and tax credits is a political issue, not a building science or engineering issue. The existence of these tax credits tells us more about the lobbying strength of the GSHP manufacturers than it does about the wisdom of these systems.


18.
Sat, 04/06/2013 - 09:57

Edited Sat, 04/06/2013 - 09:58.

Grandfather's article
by Mike MacFarland

Helpful? 0

Loved your grandfather's article on heat pumps, Martin. I was surprised by the COP between 3 and 4 back in those days, and wonder what OAT he was referencing and how it compared to today's (47F).

As we study the actual delivered performance of fully ducted air source heat pumps, and use that data as feedback to do things better, HP pros can install very simple machines that are inherently inexpensive, durable, easily serviced and maintained, and perform extraordinarily well in average to harsh climates. Average COP's between 3 and 5 with ducted distribution systems delivering 90% or more efficiency are very common and possible, even when fully concealed in unconditioned attics.

You pointed out very well the lack of data proving the actual delivered performance of ground source heat pumps as justifying the additional expense, as well as how improving enclosures further impacts the cost effectiveness. I wouldn't argue that GSHP technology doesn't have it's place, but I doubt I'll ever find that it's the best tool for the job where I live.

Good article, and your Grandpa is surely very proud. :-)


19.
Sat, 04/06/2013 - 19:56

Geo that makes sense
by David Meiland

Helpful? 0

At the Seattle Zoo the other day, I noticed a display that explains the ground loops serving the penguin exhibit, which mainly consists of a large amount of water that needs to be at ~50 F year-round. From what I've read, the install cost was around $200K, but the operating cost is very low, especially compared to the gas heaters and refrigeration equipment that would normally be used.


20.
Sat, 04/06/2013 - 21:50

DAvid: that kind of situation
by Jin Kazama

Helpful? 0

DAvid: that kind of situation exactly describes the problem and the good about GSHP.

With very large energy requirements, the cost of the system VS it's COP and possible output can make it worthwhile.

But if you need that much energy in a residential situation ..well ...

With current building methods, the loads should be lower than what would be required to render a GSHP system and its complexity inadequate.


21.
Sun, 04/07/2013 - 04:09

Edited Sun, 04/07/2013 - 04:39.

the emperor has no clothes
by David Butler

Helpful? 0

Thank you Martin for writing this. Even if we take efficiency ratings at face value, geo doesn't generally pencil out unless most or all of the following are true:
* no access to natural gas
* relatively balanced heat / cool loads
* competitive pricing
* suitable soils
* state and/or local incentives above federal tax credit

With closed loop, soil characteristics are a wild card since thermal conductivity testing isn't cost justified on small residential projects. In many areas of the country, soils can vary dramatically from one neighborhood to the next. Are you feeling lucky today?

I'm currently working on two projects pursuing open loop geo. Open loop is much less expensive and efficiencies are higher, but it requires careful attention to water quality. And regulatory hurdles can ruin your day.


22.
Sun, 04/07/2013 - 05:37

Response to Mike MacFarland
by Martin Holladay, GBA Advisor

Helpful? 0

Mike,
Thanks for the feedback. Unfortunately, I can't ask my grandfather any follow-up questions about his 1948 article. He died in 2001 at the age of 98.


23.
Sun, 04/07/2013 - 05:40

Response to David Meiland
by Martin Holladay, GBA Advisor

Helpful? 0

David,
Thanks for the information you provided on the system that maintains the water temperature at the Seattle Zoo's penguin enclosure. That's good information to keep in mind for all GBA readers who need to design penguin exhibits.


24.
Sun, 04/07/2013 - 05:43

Edited Sun, 04/07/2013 - 05:45.

Response to David Butler
by Martin Holladay, GBA Advisor

Helpful? 0

David,
Thanks for pointing out that soil characteristics can be a wild card when it comes to GSHP installations, and for pointing out that open-source drilled wells often require environmental permits.

GSHP installations almost always require engineering, and sometimes require environmental permits -- unlike ductless minisplit systems.


25.
Sun, 04/07/2013 - 09:18

All good points, but GEO has a place at the table
by Curt Kinder

Helpful? 0

I really enjoyed Grandpa Holladay's article about heat pumps in general. His use of language and ability to explain technical topics is a caliber of writing not often seen today. My dad worked his way through school in the 50s writing as a correspondent for several major mid-Atlantic newspapers, and my mom is a retired English teacher, so I was steeped in appreciation of sound writing.

We install geo (and ductless minisplits) in Florida. Both have their respective places along with traditional ducted splits. Geo shines particularly bright at the beach where 3k SF+ houses often have two or more air source systems whose outdoor units die early under the continuous onslaught of windblown sand and salt. Beach folks typically won't buy anything above code-minimum efficiency air source systems as a result, widening geo's advantage despite higher installed cost. It's a niche product / system as has been repeatedly noted above.

Ductless is great - superb efficiency, whisper-quiet operation, relatively inexpensive and easy to install. It falls flat on its face when clients don't want to look at the heads. It also fails when a load calc reveals many smaller rooms needing just a bit of conditioned air - laundries, walk in closets, pantries, small bathrooms and the like. I can't sell clients on the idea that such rooms not receive conditioned air.

There is little market in my AO for discomfort or deprivation, real or perceived.


26.
Sun, 04/07/2013 - 14:28

Edited Sun, 04/07/2013 - 14:31.

No good deed goes unpunished
by John Holahan

Helpful? 0

As a home builder, I'm continually striving to offer my clients the best alternatives for home performance balanced with the costs to deliver. We use an excellent HERS rater for HVAC system design as well as proper construction techniques, insulation and air sealing.

About 1995 or so, I met Dr. Eric Burnett at Penn State as well as Joe Lstiburek, John Straube, Achilles Karagiozis and others. They were all involved in the "Building Science for Building Enclosures" research and I became a convert. I've read all I could understand on the subject, and what I didn't understand, I could seek advice from Dr. Burnett.

Now, 18 years later, I'm still researching HVAC systems, refer to Allison Bailes at Energy Vanguard 2 or 3 times a week, joined RESNET, read a multitude of residential blog postings, follow Ted Kidd as well as his supporters and detractors, attend seminars, webinars and recently just for fun, read a book by Dan Holohan on "Radiant Heat".

Now my dilemma; I know it's too late to follow most of my fellow builders, take the easy path and just provide what ever has the best marketing department and advertising campaign.

I'll to continue my quest to offer my clients their best options for home performance, I just wish I was more comfortable with the "residential industry's" ability to deliver better guidance.

PS. I have a cabin in Woodbury, VT; may move there one day!


27.
Mon, 04/08/2013 - 06:41

Edited Mon, 04/08/2013 - 06:43.

Response to John Holahan
by Martin Holladay, GBA Advisor

Helpful? 0

John,
Let's see: about 18 years ago you met Dr. Eric Burnett, Joe Lstiburek, John Straube, and Achilles Karagiozis. You've been reading their writings and following their advice ever since.

You have also evidently been performing good deeds.

All of this sounds good. I'm not sure why, however, you are complaining that these good deeds were punished.


28.
Mon, 04/08/2013 - 06:55

Response to Curt Kinder (Comment #25)
by Martin Holladay, GBA Advisor

Helpful? 0

Curt,
I'm glad you enjoyed my grandfather's article.

Thanks for pointing out that a GSHP may make sense for ocean-front homes where the salty air can damage outdoor equipment. I agree that a GSHP may make sense in these locations -- although the cost still remains high.


29.
Mon, 04/08/2013 - 16:21

Edited Mon, 04/08/2013 - 16:31.

re: No good deed goes unpunished
by John Holahan

Helpful? 0

Martin, perhaps this was a poor choice of subject title. My complaint is that The Science of Building Enclosures appears to have consensus among the experts, yet the HVAC industry still bewilders and confuses the intended end users. I've depended on advice from vendors and suppliers who were either uniformed, complicate in their guidance or just ignorant. For years I may have, and in some cases am sure, installed over-sized equipment with poorly designed ductwork in panned stud cavities. And we weren't using the low cost provider.

Of course we know better now, but presently I'm concerned about the GSHP and ASHP systems that we thought were best serving our customers needs.

I'm looking for an easier, more trustworthy method of selecting a system that best suits the needs of my customers instead of being sold a system that sounds most plausible yet specious.


30.
Mon, 04/08/2013 - 18:50

Affordable GSHP
by Mark Attard

Helpful? 0

We have worked with a group here in Boulder that installed a 1-1/4 ton GSHP all in for less than 20k. This was before any tax credits were applied. The system included drilling for one source loop, furnace, ERV, ducting etc. The home was approximately 2,000 square feet. The key was building with a high performance building envelope and windows. The peak load was just below 14 kbtu. Design temp was 68 degrees f. The high performing windows allowed the duct work to be fat and short. There was no need to bring heat to the windows. Ducting could be run to the room instead. Air infiltration was also very low, below 1.0 ach 50.


31.
Mon, 04/08/2013 - 22:34

Edited Mon, 04/08/2013 - 22:56.

Only one data point, but...
by Scott Smith

Helpful? 0

"Now that a few ductless minisplit units can heat or cool your home with an average COP of 2.0 or more, residential ground-source heat pumps, like solar thermal systems, just don't make any sense."

170 year old 1400 sq. ft farmhouse in climate zone 6. Not an open enough floor plan to make ductless work well.
Most of the low hanging insulation/ air sealing has been addressed, but more could be done at much higher cost.
No access to gas.

We put in a 3 ton gshp 2 years ago. Total cost was 24k before tax rebates. This included desuperheater and replacement of all duct work, adding ducts as needed, and a whole house humidifier. System was estimated to pay for itself in savings within 7 years (taking tax credit into consideration). Our electric costs over each of the last 2 heating seasons have been $300-$400 more than our electric cost was prior to the addition of the gshp (this is .12/kwh electricity purchased as wind power). This replaces approx $3000+ of fuel oil we would have used each season. We're on track for 7 year payback (probably less). These are real numbers from a real installation. Then there are the asthetics, like temp control within a degree of setpoint, no setback of thermostat needed, excellent air filtration, whole house humidification as needed, quiet operation, and central air conditioning in summer when needed (without even noticing it in the electric bill). So I've gotta disagree with your statement I quoted above. There are many similar examples of old housing stock where gshp's would make sense, as well.

I too, would like to see some good studies of residential gshp installations out in the real world.


32.
Mon, 04/08/2013 - 23:52

in response to John H.
by David Butler

Helpful? 0

John Holahan wrote:
"I'm looking for an easier, more trustworthy method of selecting a system that best suits the needs of my customers instead of being sold a system that sounds most plausible yet specious."

Since you asked, here's an easy answer. Hire a 3rd party mechanical expert to make this determination. Someone with no skin in the game. In full disclosure, that's how I earn my living. When I prepare a mechanical specification, it is optimized for the particular home, site, and energy mix, and allows the client to obtain competitive apple-to-apples bids from otherwise qualified mechanical contractors. Or you can spend the 15 years it took me to acquire the experience and technical skills necessary to do what it is that I do.

David Butler
Optimal Building Systems


33.
Tue, 04/09/2013 - 04:12

Edited Tue, 04/09/2013 - 04:14.

Response to Mark Attard and Scott Smith
by Martin Holladay, GBA Advisor

Helpful? -1

Mark and Scott,
Congratulations to both of you -- Mark for the $20,000 system, and Scott for the $24,000 system. Mark's system is small (1.25 ton), but that's good, as long as it satisfies the load. Scott's system is two years old, so costs may have risen since then. But both systems sound successful.

If any GBA readers can find a GSHP contractor to install a system at the bottom end of the cost scale, as Mark and Scott have, then the economics begin to make sense -- as long as the system is well engineered, well installed, well commissioned, and untroubled by maintenance issues.

Far more typical, unfortunately, are systems that cost $35,000 to $45,000 -- and are haphazardly engineered and not necessarily commissioned.


34.
Tue, 04/09/2013 - 08:01

Performance Matters
by Mark Attard

Helpful? 0

I think what is important to note is the overall peak load requirements regardless of what HVAC system is specified or desired. In order to achieve the peak loads required for such a small system great care should be taken in designing the envelope with respect to the weather zone of a given project. In the example I mentioned, in my previous comment, an r- 40 wall was paired with r- 9 windows and an r- 80 attic. Also a minimum of r-25 was used below grade. Because of the excellent thermal and air infiltration performance of the envelope we were able to reduce the peak load requirements, thus reducing the size and cost of the HVAC system. We did not rely upon Manual J to size the system either, but rather, some other modeling software that took into account other mitigating factors. This is important because Manual J tends to oversize by about 30%.


35.
Tue, 04/09/2013 - 13:27

Response to David Butler
by John Holahan

Helpful? 0

Thanks David, I do prefer your suggestion of the 3rd party expert. I will heed the following advice.

"The way to get started is to quit talking and begin doing."
—Walt Disney: American film producer, director,
animator, entrepreneur, and philanthropist


36.
Wed, 04/10/2013 - 06:04

Another data point
by Curt Kinder

Helpful? 0

My own geo system, commissioned in 2008, heats and cools a 3400 SF house in north Florida for just under $400 per year, and its desuperheater covers about half the water heating energy for a family of 4 1/2 people, saving another $100 or so (finishing water heater is an HPWH). Both geo and HPWH are submetered, so I'm confident of the above data.

Installed cost with 4 zones and metal ductwork (uncommon here) was $25k. It uses existing artesian flowing well pressure, so low water side costs. A second recharge well and dedicated pump would have pushed total cost to $35k or so.


37.
Wed, 04/10/2013 - 21:49

Energy Piles
by Neil Tarr

Helpful? 0

Another situation when GSHP's are economically viable is when the building requires piles for structural reasons. If Piles are required anyway, water piping can be incorporated into the piles for heat transfer. They are called energy piles and there are some article on the web where they have been incorporated into some houses but mostly larger commercial buildings. It's an interesting concept.


38.
Thu, 04/11/2013 - 08:55

Respectfully Disagree
by Bryce Cramer

Helpful? 0

Martin
While I've always respected your opinions and thoughts on building science, I have to respectfully disagree with you on this one. While in your part of the country, costs may be as you describe, in the mid-west they are not nearly what you depict. I just finished two years ago with an energy efficiency rebate program for a variety of improvements. One of these was GSHP, with 31 units installed. The average cost and size was $18,260 and 3.48 tons, or approximately $5,200/ton. I will admit not all of these had duct installations, however some did. If we take that into account and increase the price to $7,000/ton, we still have an installed cost of $24,360, far less than the $42,000 you state. I would suggest that you may have contractors that are making these things far more complicated than necessary and are pricing themselves out of the geo business as they'd rather do the tried and true cookie cutter systems they've installed for years. I had geo installed in my 1,800 ft2 home (plus a finished and conditioned basement for 3,600 conditioned ft2) 22 years ago. For many years I had the system submetered. We would use on average about 3,000 kWh per year for heating and AC....and as I have whole house ventilation, we never opened doors or windows, it is conditioned space 24/7/365. Two years ago I replaced the system as I wished to have a two-speed compressor. While I have removed the metering system, my utilities meter indicates that my energy consumption has decreased from the previous system.
In the Midwest, we've been seeing successful GSHP installs for many years. And the prices I've quoted do not even include rebates or tax incentives. Maybe instead of trying to kill the product, you should consider retraining the installation folks.PS...i'm not on the installing side, I work for a utility.


39.
Thu, 04/11/2013 - 09:08

Response to Bryce Cramer
by Martin Holladay, GBA Advisor

Helpful? 1

Bryce,
Thanks for sharing cost information from the Midwest.

As I wrote in response to a previous comment: If GBA readers can find a GSHP contractor to install a system at the bottom end of the cost scale, then the economics begin to make sense.


40.
Thu, 04/11/2013 - 09:34

Passive GSHP
by Ed Dunn

Helpful? 0

A few years ago, I heard that an Earthship installed a passive system for cooling during the summer months. It probably cost just a couple hours of back hoe time (in cinder-soil) and whatever the length of 2" PVC pipe cost. Maybe total cost between $200 to no more than $500? When the space heated up during the day, a window is opened and the warm room air passively drew the cool air from the open pipe into the room. No equipment of any kind. Winter months, I suppose the pipe was capped and the passive solar energy heated the space.
I have never heard how that system worked. Anyone familiar with this idea? Are engineers, once again, overthinking a good idea? :-) (emoticon for Martin)


41.
Thu, 04/11/2013 - 09:44

Response to Ed Dunn
by Martin Holladay, GBA Advisor

Helpful? 0

Ed,
This type of duct is called an earth tube. Earth tubes have been around since the 1970s -- or probably even longer. Many people have tried them, and many installations have been problematic.

Here is a link to an article about a recent earth tube disaster: Belgian Passivhaus is Rendered Uninhabitable by Bad Indoor Air.

Other links:

A Passivhaus with an earth tube: The First U.S. Passive House Shows That Energy Efficiency Can Be Affordable

Buried fresh air intake

Geothermal house air supply

Visiting Passivhaus Job Sites in Washington State (See comment #32.)

Earth tube for make-up air

Earth tubes


42.
Thu, 04/11/2013 - 10:15

How much electricity can you buy for $41,552?
by Charlie Gould

Helpful? 0

Always find your papers interesting. I'm not sure if my numbers are right, but I believe a 4-ton heat pump which is what you discuss would put out about 45,000 btu or 13.5 Kilowatts of heat if the earth is at around 45 to 50 degrees. This for the paltry sum of $42,000.

Now I can buy baseboard for about $32 per kilowatt or about $448 for and get 14 kilowatts of heat. So how much power can I buy for the difference? And the present value of power over the life of the system? Considering the heat pump people tell you to have supplemental heat I may be buying the baseboards anyway.

The gentleman who ran Power Smart in BC about 10 years ago always claimed that the cheapest system over the first 12 years was baseboard, all due to the upfront cost.
Charlie Gould


43.
Fri, 04/12/2013 - 16:15

interesting point about baseboard, Charlie
by David Butler

Helpful? 0

in Jan 2007, Home Energy Magazine published an article about a high performance home in Ohio with electric baseboard. The owner realized that a central heating system didn't make sense in his case. The magazine initially refused to run the article because the review board felt it sent the wrong message. But the author persevered. As it turned out, the article drew an unusual amount of positive feedback and the author, Allen Zimmerman, now serves on Home Energy's Editorial Advisory Board.

I love that story. I often tell clients that the more efficient you make the envelope, the more difficult it becomes to justify the additional cost of high efficiency equipment. Mechanical contractors hate this message. After all, if their highest performance equipment doesn't make sense in a high performance home, then when does it makes sense? Exactly.

But any broad-brush statement regarding baseboard is nonsense. It depends on the load and local energy costs.


44.
Sat, 04/13/2013 - 09:09

David Butler !!!!!
by Jin Kazama

Helpful? 0

And here you come and serve...

Very well said and pointed out ...


45.
Mon, 04/15/2013 - 13:49

My Take on the decision matrix
by Karl Overn

Helpful? 0

Just to expand on David Butler's point I think it comes down to a 2 x 2 matrix with "Building Envelope" and "HVAC Equipment".
----
Quadrant 1 - "Low efficiency, low cost envelope" and "Low efficiency, low cost HVAC"
This is what we've been doing. HVAC equipment should be simple and reliable. Highly sensitive to rising energy cost. Good only with low cost energy and low environmental awareness.
----
Quadrant 2 - "Low efficiency, low cost envelope" and "High efficiency, high cost HVAC"
This is good for retrofitting an existing structure especially where changing the envelope is difficult. ROI still depends on energy cost (electricity in the case of GSHP) and equipment longevity / performance.
----
Quadrant 3 - "High efficiency, High cost envelope" and "Low efficiency, low cost HVAC"
This is just adding insulation and air sealing. If done properly the cost is one time only and performance / longevity is stable and predictable. HVAC equipment should be simple and reliable compared to GSHP. Less sensitive to rising energy cost than quadrant 1 or 2. Changing or replacing HVAC equipment is easy as conditions change over the years.
----
Quadrant 4 - "High efficiency, High cost envelope" and "High efficiency, High cost HVAC"
A waste of money. Pick one or the other.
----
Obviously I prefer Quadrant 3 for new construction and retrofit, but equipment like GSHP does have applications.


46.
Tue, 04/16/2013 - 01:27

Karl, interesting take...
by David Butler

Helpful? 0

but your choices are too binary. The optimal solution according to your matrix will always fall in between quadrants, depending on local energy price mix as well as climate zone (which you didn't mention).

In particular, I think we should be starting from a mid-efficiency baseline. For example, I would never specify an AC or heat pump with a PSC air handler. Upgrading to non-variable ECM is a no-brainer and automatically gets you to around 15 SEER.

Still, I like the concept.


47.
Tue, 04/16/2013 - 08:53

Edited Thu, 04/25/2013 - 03:12.

GEOTHERMAL Heat Pumps for retrofit and new homes
by JP Jon Pierce

Helpful? 0

RIGHT I pasted with wrong solar comment window up after correcting in word for spelling...

~~~~~~~~~~~~~~~~~~~~~~~~~

I spoke with Dr. Steve Kavanaugh 6 years ago
because I found few were guaranteeing loop EW at 2.8 gpm per COMPRESSOR-IN-BOX TON, of 34f to 35f in northern 53-50-deg ground applications. Since 1983 implementing such, so many "experts" blathered I undersized units, but the units heated in zone 5-6 well to zero and below ( a few ~ 5-7 deg balance to needing supplemental) . Then I wrote PERFORMANCE contracts of "34 or more" saving money on equipment was allowable because the loop is warmer and these "chillers" are more efficient on warmer loops: like ANY air source refrigerant auges read on a 40-degree day or warmer, HX to compressor stage/ apples to apples.

Now having HANDS ON 300+ GT Well-Water open systems ((one NOT NECESSARILY must bore a hole- STILL TODAY)) -
GT units and ones I have reviewed others installed with apples to apples deducting well distributed ducting that is , and deducting costs of "going to do anyway with any HVAC-HW" ---
common plumbing and HW tank are then with Priority all-inclusive.
$16000 costs of a Mitsubishi 5 ton applicable minisplit or high eff heat pump and high eff propane gas (ducted or radiant)... and a 5000 to 8000 comparative tax credit and ut'y co rebates...simply has had these
GeoThermal Earth-Heat Exchanging Systems have com in as a LOWEST first cost .
Noting also the more so on a well that qualified and quantified in 3 to 4 days tests at under 50% draw down of static waters--- not to lift over 110ft usually.::
Adding closed loops of now still complete under $1600 per AHRI rated ton (1800-$1900 with flowcenter and reservoir complete) even per COMPRESSOR-Ton (C-t) on w:w is a great ROI , I believe.:
~ ALL-COSTS-CENSORED/accounted for, leaves us only finding nice: 4 and 5 year COMMON ROI's. ((sometimes the LOWEST first cost, removing all non-geothermal items of say a boiler or other water heaters or a bunch of MINI Splits and still have cold feet, not as with ducts that do radiate to flooring also)
GENERALLY accounting for all:
I see 20% of the remaining 4000-6000 dollar variations of difference leaves w/inflation, 10-12 year returns way over $10,000. Plenty to replace meager parts installation and OEM deficits.
In to losing credits in 2016 those will be 6-10yr ROI's...

[better - return air systems] gas or GT HtP both need this generally in all retrofits especially..

I believe, which in 25 to 35 year concurrent lifecycle studies of the VERY LOW MIANTENANCE I have had with over 300 well-open 'loop'
and out of 1600 hands on (maybe 1700 geothermal calls to commercial and schools etc and process cooler to preheater industrial ECL, GLE loops) -- are to be expected.

The Air-Solar (see some recent comments at 2011 and 2012 posts of older HW and Solar thermal...)
The Air Solar- of 1980, instructions is why I put in only a little more effort to sealing ducting since 1983 for all my HVAC like those solar systems.
WOW! 3 ton compressors in 3000-3400 sqft over uninsulated basements zone 5.1/2 (1994 peaked -18f below there).

~
NOW: with the Hydro-Temp patented HW 100% On-Demand Priority and RECLAIM 100% in cooling since 1981, and their first in the country net-zero-school, and blowing away so many in 2008 study retrofitting a stick-built to a near by compared Gas-HeatPump school showing 50% savings on all accounts...
THEN they were at their HIGH 1.8kw per sq ft per school year (other GT at 2.3 to 2.1, compared)...!

I used their variable ECM 1 blowers on dual compressors (sm+lg, then both for 3 staging) since 1996 and with oversized HX coils hitting 2010's efficiencies in the 90's.
SAVINGS DRAMATICALLY VARIES with full Heat-Reclaim (loop pumps OFF) during HW recovery in AirConditioningCooling mode.

Well see the un-rated Hydro-Temp com for yourselves. since the 80's, that's 480 watts on 8 to 9 compressor-tons(C-t) ) which is like 22 or more "RATED-Size 'tons' "per pump horsepower if more efficiently piped at the loop, etc. building headers for flushing but operating under 22ft Wtr TDH by design.

Any Q's , please point to the line; and not general grammar, please.


48.
Tue, 04/16/2013 - 09:13

Edited Thu, 04/25/2013 - 03:23.

Affordable Geothermal or 20yr ROI radiant ?
by JP Jon Pierce

Helpful? 0

IF you were to picture what I did in 2007 at a 4 zone radiant residential system in Harrisburg PA it is quite different than posted above (Mr Gadgeet looking things above).
A simple oversized header loop of 1.1/2" and three pumps hanging below the feed - bottom-header with one tempering valve has no need of a reservoir because of Dual-Compressor 3-staging used 2t+3t for 5 is of a more load-matching: A first hottest zone is 17,000 btuh output at ~ 115 deg and so the first compressor staging on at 2 tons runs a long time before cycling at a reasonable design. [now residential IQ Variable V-Star compressors have replaced duals to under 7.1/2 tons as of March 2013, here described above, a 4.1/2 ton V-Star by Hydro-Temp of AR, not hydrodelta-hydroheat, would fit nicer even at 25% first staging ~ 14,000 btuh, ramping to load matching by programmable temperature controller settings (all IRD Wireless since 2007 for the controller)]
NO radiant loop storage tank.
Hottest first zones off header first. (saving plumbing)
w/ one full rec-area basement mixing valve.

FORCED AIR Heating and cooling from ONE GT System-unit...and domestic FULL INSTANT On-Demand by temp control/ OEM HVAC+2 HW exchangers.

Simple continuous 1.1/4" x 800ft Vert-Bore ground loop (stays over 34EW in zone5)

Walk-out basement in 2700 other living sq ft @ $ BUDGET $93/mo
for a couple of years running, was in insulated walls of cellulose insulated standards.
300 sq ft glass.
This year might break $100/mo budget: ALL UT'y HVAC+HW+HOME.
3nd and 4th year some light maintenance by the owner with internal on-off of the water pump accessable : flush Domestic Coil for HW with vinegar each two years/ change air filters once/year.

a defect up front was - Found loop circ pump (like any boiler application) OEM defect, the owner replaced quickly. ( he built his own duct system completely of buct board and flex throughout, I designed with his material choice to be appeopriate to concerns of resistance calcs.

ECM Air circulation with proper return air system cleans the air from most dust 24/7 4" pleats, at the low blower (adjustable by Infra-Red-Palm controller) etc etc.
Radiant: Living room 115 degree 1st zone, other 1st flooring 111 deg; and 109 deg 2nd floor, third zone and 4th zn : 78 deg to basement.

This can be done with W:W unit and a Forced Air combined, or W:W with HVAC fancoils , but was not here so needed as the HVAC Double Prioity is : All one unit 34x32 footprint 74" tall
MOSTLY AFFORDABLE WHEN ACCOUNTING FOR (Censoring means to "ACCOUNT") ABOUT SAVINGS:
( DUAL Proiority HW 100% on-demand and 2nd Radiant Priority / OEM 4 zone boards since the early 90's... nor multi-=programmable and here a first IRD Wireless logs and snesors read and programming since 2007 for various water temps and air speeds and regulated bonnet temps selectable for Air Distribution Variable load Matching comfort at a highest savings found among GeoThermal [ which is why you see adv of others 'highest RATED eff in the world] hydro-Temp meeting all COMPLIANCE with ENERGY STAR(tm) has never been rated and surpasses requirements each year. I ordered this unti in 2007 with 2-ton oversized coils for superior efficiency.

... and now residential IQ Variable Compressors 2.1/2; 4.1/2; and 6 tons on the compressor label.(like some AHRI-Rated's at "7-size-tons"...wont run in to the Dr Steve Kavanaugh censorship which only exposes truths of "rated' systems)

The DeHumidification of 3 Stages and in now Variables is second to no single or two-staging compressor.
This installation assisted by the owner @ 17,000 plus radiant zones he installed himself, was nearly 6,000 less than all by a local installer. TOTAL electric bills of under $100./mo? in a walk-out basement? WOW! That's why he sends Harry and Davids gifts at Christmas- , you really can give a customer what they want and what they needed and comfort they did not ask you for !


49.
Tue, 04/16/2013 - 09:14

Edited Tue, 04/16/2013 - 09:16.

Response to Jon Pierce's Comment #47
by Martin Holladay, GBA Advisor

Helpful? 0

Jon,
You wrote, "Any Q's , please point to the line; and not general grammar, please."

I don't think that I have any questions. It really is hard to wade through your prose, which doesn't conform to most methods of speaking or writing.

A few comments:

You wrote, quoting from a different blog of mine: "But it's time to admit that a PV array is cheaper and less troublesome than fluid-filled solar collectors on your roof." I'm not sure what relevance this quote has to the article on this page.

Examples of opaque sentences: "one or two duct discharge to warm air space heating changeover when winter HW is 'FULL' ! Air collectors of 3-layer window screen 3/4 inch separations of an OEM baked 500f charcoal gray." I really have no idea what you are talking about, but it doesn't sound like you are talking about a ground-source heat pump -- the topic of this blog.

You wrote, "has occurred through and to ALL-COSTS-CENSORED: 4 and 5 year COMONLY CALCULATED ROI's." Why were costs censored? Who is censoring?

You wrote, "Radiant in-floor all over is 20+ year ROI's." Why would a heat distribution system (PEX tubing in a floor) have a return on investment? Compared to what? Fin-tube radiation? Both systems deliver heat -- but PEX in the floor usually costs more than fin-tube. I have no idea what "return" (on the investment of in-floor tubing) you are talking about.


50.
Tue, 04/16/2013 - 09:21

Edited Tue, 04/16/2013 - 09:36.

Response to Jon Pierce's Comment #48
by Martin Holladay, GBA Advisor

Helpful? 0

Jon,
I'm still lost.

"The picture ... is quite different." Different from what?

What does "$93/mo cellulose" mean?

What does this mean: "ALL UT'y HVAC+HW+HOME"?

I thought I was getting close when I guessed, "All utilities including heating, ventilation, air conditioning, and domestic hot water." But then I was completely stumped by "+HOME." This type of arithmetic sum is beyond my comprehension.


51.
Tue, 04/16/2013 - 22:41

Edited Tue, 04/16/2013 - 22:42.

Martin, why not just hit the delete key...
by David Butler

Helpful? 0

saving readers from having to wade through this off-topic nonsense? Fortunately, in my group on LinkedIn, I've never had to deal with a comment so, well... incomprehensible.


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