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Geo-thermal survey

Our house is located in Putnam County, NY and dates to about 1830. We have steam heat which is pretty efficient and we like our old radiators. Last year we installed a Unico central air conditioning system. We installed the entire system by ourselves so we know it well. Unico is an amazing system. We air conditioned the entire house without disturbing any plaster. We have air conditioning in one part of the house that we are unable to heat. It was difficult and challenging but we were able to get the duct work to these rooms. We would like to do a Geothermal system using the Unico system to get heat to these rooms in the winter. We would keep our steam system as a back up for extremely cold days. Has anyone ever used a Unico system for Geothermal? We are very interested in alternative energy for our home. We started with our diesel car and converted it to run on 100% vegetable oil. We now need to address the house.
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Comments

  • singh
    singh Member Posts: 866
    Questions

    A quick survey,
    has anyone here installed these systems, if so
    how did it go?
    how many installs?
    was it water to water (radiant)? cooling?
    Any pics?
    Are you certified, by manufacturer or IGSHPA?
    Did you invest in equipment? hire subs?
    vertical or horizontal loops?
    Are you seeing a rise in inquiries from owners/builders about these systems?

    Just asking, I had two recent inquiries and on a personal level would like one should I ever build a new house. One project sounds promising,earth sheltered , passive, radiant etc..
    Next week I will attend a factory class and next month IGSHPA (same week as HCT Las Vegas) :(
    I am also in a ag./rural area and a min. of 3 acers per single family home is typical, so barring soil conditions , horizontal loops may be feasible. I did replace a storage tank (water heater) once for a customer with Geo. water to air and he loved it. The only other install I know of close by is the community college campus, but I don't know of any other contractor in area. May be a new avenue for me.



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  • I will predict right here and now...

    that heat pumps and condensing boiler hybrid system will become the standard for super efficient home heating systems. Superceding even solar.

    Combination air, water and a mix of solar can result in significant energy cash outlays. It requires a significant dolar outlay up front, but the energy sources are free.

    I've read reports on the net (google deep earth energy storage) and they say you can get 80% back out of the ground that you put in. I'm thinking that in perfect situations, a person could eliminate their dependence on gas or oil. And it can be powered by solar photo voltaic.

    As for certification, the class I took was horrible. The instructor didn't have any routine down and was blowing through slides saying "You don't need to see that, click, You don't need to see that, click..." I WANTED to see that, that's why I came...

    Any more, I look at certification by ANY organization and say that in court, they don't give a crap about WHAT certifications you've got, and people have never called me and asked, "Are you a member of the RPA?", or asked for either of the two certifications I held there. I get more calls from ARP then I do RPA for crying out loud:-)

    Key word, had. I'm letting them lapse. Of no earthly good to me in my day to day business.

    In fairness to them, I'm not giving them a chance, or promoting that fact. I don't promote any facts other than my professionalism. I don't flash my masters plumbers license, which I still carry, and HAVE been asked to produce NUMEROUS times, by the same inspector, who also carries a masters license, and shows you his...

    But to do geo right, you gotta understand the basics, like soil conductivity, average earth temperatures, impact of moisture. Based on my folowings of you on this site, I'm confident you can handle the system. Installation generally requires designs around temps of 120 max for the geo, but if you want a hybrid, you can do splits. In Colorado, a 50-50 split works well. The GEO ends up doing around 70 to 80 percent of the load.

    I find that the insurance, and equipment plus maintenance and operators costs for doing major underground work (excavation) (this stuff is DANGEROUS) can and should be left to specialist in that field. I have a sub contractor that I use that does my loop fields for me up to and including the GEO heat source. I then treat it like a "heat source", dump it in and let 'er rip. The use of non electric TRV's on high mass floors is preferable. It is not conducive to set back, so conservation (tight homes, super insulated or earth linked) is a must.

    As for air collectors, there are experiments going on right now, that use air for 75% of the energy source, running at a high COP due to elevated temperatures. That, coupled with a building ventilation system via wells size for cooling only, could conceiveably be 100% geo and have an air conditioning system that basically becomes a waste heat recovery system.

    Yeah, I think you could handle it...

    We've got two geo jobs coming up this summer , possibly three that are lake systems. One is unnatural and two are naturals. Imagine building a lake to heat and cool your house... There are people and places doing it. Have been for quite some time. You want to make sure you have strong water rights...:-)

    Use super highly efficient heat emmitters like WarmBoard or one of the others. The lower the operating temperature, the more efficient the heat pump is. The higher the source water temperature is, and the lower the load temperature is, you can conceiveably break the 4.0 COP barier on a regular basis.

    Times, they are a changing. Once gloabal warming kicks in, this type of system will be come mandatory. That is my humble opinion.

    ME
  • Gary Hayden_2
    Gary Hayden_2 Member Posts: 61
    Mark is right on!

    Amen Brother. I went to the Milan show and this was the standard MO for the appliance suppliers: Condensing boilers, solar and geothermal.

    www.ecrtech.com
    www.schueco.com
    www.triangletube.com

    BTW - Imagine this - life size fooseball game. Miss Italy 2003 and 2004 (not sure about the years but you get the point) running the game. European contractors (that grew up playing soccer) attached 3 and 2 etc to a pole (simulation of the pole that you turn with your hand) kicking a soccer ball. The players had to work together to move back and forth to get to the soccer ball since they were nylon belted to the pole and had limited movement. One of the Miss Italys would assist those that had trouble with the belt to the pole:) - I saw a lot of guys having problems asking for assistance:). What a kick :) It was all clean fun. This was just one of the many different ways companies entertained at the Milan show.
  • Supply House Rick
    Supply House Rick Member Posts: 1,404
    Devan

    WE also think it's the next big thing. We have taken on a Geo line and are having an extensive training course in Fishkill. Will send you info on Monday when I get back to my office. Check your email Monday...

    Rick
  • singh
    singh Member Posts: 866
    I have a hunch

    you're right Mark. Many will look for ways to be less dependant on oil/gas for heating/dhw in the very near future. Geo is one of them.

    I agree certifications from whoever are NOT the only way, I'll even say lic. are not the end all either. What does matter is professionalism, and if you stand in front of your work (not behind) :)

    However, certs. are just another ave. In the short time I've been a member of RPA, I had calls/email looking for someone who IS a member,cert. etc.. Just may be a result of demographics and available contractors willing to do the
    job.

    Thanks for the vote of confidence, Mark. I did not know I had a following on the wall :D but I follow your wise and informative posts/columns closely also.

    "Once global warming kicks in" I think its here. And that's my humble opinion.

    Devan



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  • singh
    singh Member Posts: 866
  • S Ebels
    S Ebels Member Posts: 2,322
    Couldn't agree more Mark

    In fact, it's already happening. I was going through my quotes and leads this AM and over 50% of them are for GSHP systems in either stand alone or coupled with a condensing boiler. Another 30% of the leads are for Bio fueled equipment of some kind. Then there are the ones with their heads in the sand asking what's the "cheapest" (Big sigh here) There are some that learn the hard way by paying fuel bills equal to their house payments. (another big sigh)

    The consumers that are asking about the Bio fueled equipment (at least the ones that come to me) are second time wood burners. They have done the indoor furnace/wood stove thing or an outdoor "boiler" and don't want to go back there. For lot's of very good reasons, I might add. They are looking for a good quality, automated wood, pellet or corn fired system. The problem is that there is very little on the US market that I would call a good quality, easy to use/maintain bio fueled product.

    I think a LOT of people see the handwriting on the wall and realize they will be able to buy fuel......but at what price. That's the scary part to them. They see fuel prices jump 10-15% based on rumor only and wonder what will happen when some idiot finally manages to blow up a Saudi pipeline or a refinery here in the US. The prudent among them realize it's a matter of when, not if, this happens and want to insulate themselves from the effects of an event like that.

    I have a gut feeling that wood pellets are going to be big. My brothers in the hardware have hooked up with a pellet extruding company in Escanaba MI and are buying them at a rate of 2 semi loads a month. Wood pellets are cheap btu's if you buy them in the preseason. During the middle of winter the price gets very close to other fuels. Close enough that your return on investment gets very skinny in a traditional 60-70% efficient pellet stove.

    Where's this all going??? It going toward the contractor that keeps himself or his company out at the cutting edge of the heating trade. The heating industry is no different than any other business in this hi-speed connected instant everything world. Change with the times or close up shop in a matter of a couple years, it's as simple as that.
  • JackFre
    JackFre Member Posts: 225
    While not having been involved with it in a long time...

    I did a bunch of systems in the late 70's with water to air and water/water. You might want to check, being in the Las Vegas area, with the CA Energy Comm. They did extensive studies all down the Eastern border of CA, as well as the rest of the state, on different types of heat transfer etc of the soil formations.If not useful for your particular area it is "more knowledge" and therefore,worthwhile. The Geo-Heat Center at Oregon Inst Tech has a great deal of info also.

    We used to heat the well covered swimming pool with a glazed solar system as the heat source for winter. We would them reject heat to the pool for a/c. The only negative there was increased chemical use due to higher temps. We also used radiant tubing to reject heat thru the concrete pool skirt at night. Keep in mind that this was N CA and the heat/cool deg days were about a push.

    For some of the ground loops, if soil conditions permit (which they seldom did) we used to Ditch-Witch a deep trench and put in Sola-Roll plastic collectors on edge and if the field performance dropped due to poor Reynolds factors we would use drip irrigation to get the heat transfer.

    Geo HP's are neat systems, BUT, you better have a GOOD guy for design, install and definitely to maintain performance.
  • GH
    GH Member Posts: 45
    GEO THERMO

    Just did our first Geo and Radiant done right project
    last fall and have watcted this project through the winter
    heating season.WOW WOW and WOW. The A.I.A. the AP press
    a ranking member of the RPA and a rep from the Geo Exchange will be on site April 6 @ 10am . Watch for the press.
    WWW.gcsradiantheat.com WWW.geoexchange.org
  • tim smith
    tim smith Member Posts: 2,738
    Geo thermal

    Worked on them many years ago in the early 80s, reworked a sand point well system that was kinda funky but worked for the coast guard. Also worked on quite a few lake loop geo units. Our main Climate master heat pump distributor here in seattle has been doing the ground loop sections for quite a while and are very well qualified in the ground section of the installs. good guys. I do quite alot of work on tower loop heat pumps and as this is very similar except for the great heat sync the ground does instead of the tower i am fairly familiar.
  • about half

    of our business is geothermal now, of that about 70% is water to water radiant floor. we sub out the sheet metal on the forced air ones.

    my company's been doing them for about 10 years, myself about 2.

    mostly horizontal loops and open well systems, a couple of vertical loops though (our shop was one of them, drillings expensive!)

    this looks like it will be our busiest year yet, prospective customer enquiries are up about 100%!

    not IGSHPA crtified (yet) but Next Energy/Climate Master certified.

    been toying with the idea of running a water to water unit off the city water main in my own house.

    a few of our customers are reporting total electric bills of $65 a month!
  • S Ebels
    S Ebels Member Posts: 2,322
    Rick

    What line and why?
  • Supply House Rick
    Supply House Rick Member Posts: 1,404
    Econar

    Why?

    ECONAR has been producing GeoSource geothermal heat pumps in Minnesota for a quarter of a century. Minnesota’s cold winter climate has driven the design of ECONAR’s heating and cooling equipment to what is known as a “ColdClimate” geothermal heat pump.

    This cold climate technology maximizes the energy savings available in heating dominated regions without sacrificing comfort, thus making ECONAR the leader in cold climate heat pump technology. Extremely efficient cooling, dehumidification and optional domestic hot water heating are also provided in one neatly packaged system. Hate to plagiarize, they can explain in better than I can. It's a new line for us and I am still learning...


    Rick
  • Brent_2
    Brent_2 Member Posts: 81
    geo

    We do mainly closed loop vertical wells. They may be a little more expensive but take a lot less coordination and disruption.
    I would like to know what they say at factory training about using open wells. I know there are a lot out there that are working fine. Our climatemaster sales rep says that he would not install one. You have the pumping energy to pay for and some water variables that could cause problems.

    brent
  • Mr. Blonde
    Mr. Blonde Member Posts: 38
    Hybrid systems

    Could you explain in a little more detail how these hybrid systems work and the setup.

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  • Craig Bergman
    Craig Bergman Member Posts: 84
    Doesn't matter

    what's in the sales pitch. It all comes down to COP and EER. Manufactures can say what ever they want...But if they claim 4+ COP and 25+ EER they have to deliver!!

    Bergy
  • Craig Bergman
    Craig Bergman Member Posts: 84
    We use

    GeoComfort. They are a small company searving mainly the Midwest AND I get GREAT tech support. The Geocomfort line is made for them by Water Furnace International. We looked at a lot of the main players and settled on WFI products for several reasons. Time in the Geothermal Heat Pump game,performance of the equipment,LOOKS of the equipment,cost and support.

    My two pennies

    Bergy
  • Xc8p2dC_2
    Xc8p2dC_2 Member Posts: 150


  • Xc8p2dC_2
    Xc8p2dC_2 Member Posts: 150
    Got Heat

    always wondered how much benifit, if in an area with low earth temps>> my area shows geo temps around 60 deg

    http://www.heatflow.und.edu/usa.jpg
  • Anna Conda
    Anna Conda Member Posts: 122


    Groundsource heat pumps are being used in Whitehorse, YK. Its mainly a matter of getting down to where the Earth's temperature is stable year-round. The further towards the poles, the deeper you have to dig, but the heat is still there. Geo is one of the few 'green' energy sources suitable for the Arctic.
  • Weezbo
    Weezbo Member Posts: 6,232
    excuse me ,Anna Conda...do you have a link

    or some accurate information on these GSHP and the depths and soil types that sorta thing?

    we have warm ,hot even mineral water springs all over the Arctic and sub arctic that could be and in some case are being used ,... at 770' we have wells that are real warm :)
  • Anna Conda
    Anna Conda Member Posts: 122


    Betcha, Weezbo. Gimme half the afternoon and I'll come up with a few for you (busy day today... ) And yes, those hotsprings sure are being used. The fish hatchery in Whitehorse is using one for their geoexchange.
  • Anna Conda
    Anna Conda Member Posts: 122
    Present for Mr. Weezbo

    Follow this link:

    http://www.mcquay.com/McQuay/DesignSolutions/GeothermalPage5

    And choose their Geothermal Heat Pump Design Manual. This should address most of your questions, and yes the soil temperatures table in the Appendix does address Alaska too =)
  • David Zierke
    David Zierke Member Posts: 19
    Geothermal is a dinasour

    I wouldn't put in a geothermal. They are to costly. The same benefits can be obtained by a Waters Hot RASERS unit at a fraction of the cost. In some applications there are heavy tax incentives. Information can be found at www.watershotinc.com
  • Craig Bergman
    Craig Bergman Member Posts: 84
    What is the

    COP and EER of the unit? Is it ARI listed?
    The up front cost of a Geo unit is higher than a gas fired unit but the cost of ownership is always lower.

    For example, a 2500 sqft home with a walk-out basement costing $250,000 with a 30 year 6% fixed rate mortgage cost of ownership would be...

    Geothermal

    $1,559 mortgage___$65 Heating__$7 Cooling__$21
    Hot water___________________________Total = $1,652/month

    92% Eff. Natural Gas

    $1,499 Mortgage___$144 Heating__$12 Cooling__$29
    Hot water__________________________Total = $1,684/month

    92% Eff. Propane

    $1,499 Mortgage___$185 Heating__$12 Cooling__$38
    Hot water___________________________Total = $1,734/month

    These numbers are based on the Geothermal system costing $10,000 dollars more than the gas fired units with a 13 SEER A/C system.

    While the geo thermal system adds $60/ month to the mortgage, it saves the homeowner about $396 dollars/year.
    Those are the numbers that allow our Geothermal business to almost double in volume every year.

    Bergy
  • David Zierke
    David Zierke Member Posts: 19


    I'm not sure what the COP is. I can tell you that my unit cost a total of $9,000 and it costs about 90 dollars a month in January and February to operate. It was a two day installation that didn't require anything done except a evaporator panel to be hung on the outside of our home and some plumbing. Then the hot water it produces is put into a tank for storage. When the house calls for heat the water is pumped thru a heat exchange unit in the ductwork. What use to be primary heat source (oil fired forced air) is now just backup heat and rarely comes on.
  • Jim_65
    Jim_65 Member Posts: 184
    COP

    Coefficient of Performance (COP)

    The ratio of heating (or cooling) provided by a heat pump (or other refrigeration device, e.g., air conditioner or refrigerator) to the energy consumed by the system under designated operating conditions.
  • Supply House Rick
    Supply House Rick Member Posts: 1,404
    Bergy vs Salespeople

    I happen to be in sales, that's how us salespeople speak... hahaha Without sales, there would be no produts. Happy April Fools Day

    Rick
  • Wayne_16
    Wayne_16 Member Posts: 130
    COP co-efficient of performance

    the ratio of energy used to move heat from a source ie (ground or air) to the building.

    Think of 1 one dollar's worth of electricity used to operate a refrigeration system moving the equivilent of 3 three dollars worth of heat into the building. COP of 3 most manufactures express there COP ratings in whole numbers and fractions.

    As others stated, the closer the heat requirements are to the heat available, the better the cop rating.

    Ground source heat pump manufactures use the lowest entering water temperature availabe for the cop ratings, so when the entering water temperature is higher than design, the cop increases.

    Go GEO

    Wayne
  • SM
    SM Member Posts: 37
    Direct Exchange Nordic

    Has anyone installed a direct exchange geo system by Nordic or any other company? My father-in-law is talking about building a new office/shop (7500 sq/ft) at the farm in two years and I am think this would be a great way to do radiant slab heat with the rising fuel prices. Could also put airhandlers in the offices for chilled water air conditioning.

    How does installation cost compare? What are the average bore depths and number of bores per ton?

    These systems seem to be a great way to go as you are eliminating a heat transfer (ground to water to refrigerant vs ground to refrigerant).

    Scott
  • Mad Dog_2
    Mad Dog_2 Member Posts: 6,719
    From what I see and read here and elsewhere

    Folks out in the country are more open-minded to trying the new cutting edge technologies than in the rich Long Island & Westchester suburbs. Condensing, ODR and solar are a very hard sell - especially with the monied set making low to mid six figures. They're outfitting their homes with 15 k home theaters and 50k in Landscaping, but really don't want to spend on the most important features of the home. I went on a sales call yesterday: Wealthy folks, 55ish. 2 million dollar home on 1 acre. Granite floors throughout. She complains that her oil bills are astronomical...and they are... and that no one can give her any answers., including the oil company I spent over an hour there showing her all the problems with the system and how we can save her mega bucks with smaller, properly sized boiler and indirect w/ ODR. Talking to a wall..."were not gonna spend money like that!!!!! That's double what the oil company quoted(same oversized boiler...no ODR...no indirect)!!!! NOBODY else told us about this stuff!!!" Very frustrating sometimes. Mad Dog

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  • singh
    singh Member Posts: 866


    No doubt those who would be interested in Geo,High eff. condensing boilers, ODR are those in the middle to lower income ranges.
    I just viewed a promo on a whole community done in geo, small homes >2000sq.ft sold to those with moderate incomes. They interviewed the bankers who backed the developers. She said if it was not for the lower energy bills,which offsets the debt-to-income ratio, most of the homeowners would not be able to own these homes.
    My view is systems like radiant are perceived as being high end options in high end homes. Those with high incomes don't NEED these systems, they WANT it. It's a status symbol, and today ranked just as high as granite counters.
    I'm afraid it will stay that way for some time, until fuel prices get way, way out of hand. We are not at that tipping point yet.
    It may be nice to get the ocassional 13,000 square foot job, but I bet you'll have more success closing the deal on a quality install in a 2500 sq.' home.

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  • Tom_35
    Tom_35 Member Posts: 265
    ECR direct exchange heat pumps

    Scott,

    We've installed a number of the ECR direct exchange heat pump systems and they work well. Their website, www.ecrtechnologies.com can provide you with a lot of info.

    Then number of bore holes and depth per ton will depend on the earth temperature in your area.

    We have used the units for conventional heating and cooling with an air handler and also added radiant heat on several jobs. You can also use their de-superheater for domestic water heating during the cooling season, or add the domestic hot water module for on-demand hot water year round.

    We will be completing a new construction home is a couple of months that has 6 ECR units on it, de-superheaters, on-demand hot water heating, and continuous circulation radiant heating.

    The ECR units are pretty versatile, but I don't know anything about the Nordic brand.

    Tom Atchley
  • Scott Gregg
    Scott Gregg Member Posts: 187
    What's in your house?

    I've read all the posts to date and enjoyed them very much. I’m wondering how many of you have Geo in your own personal homes.

    I am about to build beginning in August and the plan is to go Geo! I’m still going to use LP for cooking, grilling and a couple of gas log sets, but the house will be a combo of geo, water to water and water to air. Radiant basement and first floor with forced air second floor. We are really looking forward to it!

    Thte house will double as a personal showcase and should be a very comfortable and highly efficient home.
  • Tom_35
    Tom_35 Member Posts: 265
    What's in my house?

    I have installed a combination of systems in my home. I added an ECR direct exchange heat pump system a couple of years ago in order to test how the horizontal heat exchanger would work, as well as the "on demand" domestic hot water module. This unit serves the radiant floor on my 3,300 sq. foot home.

    I also have a 75,000 btu condensing boiler (93%) that is branded by Carrier, but made by a company that I don't recall at this time. The boiler is still installed in the hydronic circuit and can be used by the flip of a switch, which takes the ECR unit out of the circuit.

    The radiant system has 9 zones, and Tekmar outdoor reset which was added when the ECR unit was installed.

    I had the ECR system down for the first couple of months of the heating season this year, so I was using propane for the boiler. When we finally got the time to complete the new Flat Plate heat exchanger, my propane usage naturally dropped to nothing, but my heating cost is half what it was with the propane.

    Tom Atchley
  • David Zierke
    David Zierke Member Posts: 19
    COP is 4 to 4.7

    I knew the definition of COP, but I had forgotten the actual numbers for the RASERS system. I checked, and they are in the 4 to 4.7 area. They very with the installation. If the condenser coil is placed in a heat stream such as discharged water from showers, carwashing, laundries, or even in a manure pit, the COP will be pretty constant on the upper end of the scale around 4.7. If the condenser is just hanging outside in -15deg farenheit air it will fall to around 4 maybe slightly less if the condenser coil ices over. Here in the Northwest corner of Iowa and the southeast corner of South Dakota we get sustained cold weather. On the coasts or farther south the units will perform better just hanging outside on the building.
    When it comes to A/C, we use an A/C coil in the ducts as the evaporator then scrub the heat we get back into the domestic hot water so we do two jobs with the same electricity. Cool the space and heat water. That water can heat a pool or a hot tub as well.
    These systems are mainly geared toward commercial and agricultural applications, but have been placed in homes and perform great there. They work great with Hydronic systems.
  • Tom_35
    Tom_35 Member Posts: 265
    You're right

    Only the rich can afford high utility bills. We find that most of our inquiries about super high efficiency HVAC is from middle income people. The folks that have a bundle of money are normally interested in what can be seen and not what is the most comfortable.

    There are exceptions, but they are certainly not in the majority. We are getting close to finishing an incredibly expensive home and it does have radiant heating throughout, 6 ECR direct exchange heat pumps, a nice IAQ system---but the difference was that the customer and the architect had experienced radiant heating in Colorado and were sold on it. Had they not actually been in a radiant heated condo, there would have been little chance that it would have been installed since radiant/hydronic systems would not even come up to a half of one percent of the market in Arkansas.

    Tom Atchley
  • David Zierke
    David Zierke Member Posts: 19
    If you are in the planning stages

    of a house or a shop for your dad, Radiant is the way to go if done right. But before you spend on Geo, take a look at a Waters Hot RASERS. There is a lot of flexibility in the istallation and everything stays above ground. I'm very happy with the unit in my house and shop.
  • Weezbo
    Weezbo Member Posts: 6,232
    Let me say Thank You First . Then, i will read ...

    when we have hotsprings and the water is constantly flowing And the water is potable What is there Not to like?

    i think the Inuiat know of these almost in the same way as the camel herders of the Sahara know of places to find water....

    that was 79 pages worth checking into
  • Kevin_in_Denver_2
    Kevin_in_Denver_2 Member Posts: 588
    RASER sounds sketchy

    My scam meter went off when you said a COP of 4 at -15F.
    I think I would have heard of this amazing feat somehow if it were true.

    As you mentioned, the condensing coil will ice up. Ice acts as insulation in this case and heat transfer stops.

    The website didn't do much to educate me. Where else can I look for info? I'm intrigued because it is theoretically possible.
    Superinsulated Passive solar house, Buderus in floor backup heat by Mark Eatherton, 3KW grid-tied PV system, various solar thermal experiments
This discussion has been closed.