Anybody know where I can get good information on sizing and installing a ground source heat pump? I posted over in “green building” but it doesn’t look like that forum gets a lot of attention.
Is this the most efficient way to heat a home?
Thanks,
Tom
This compact detatched accessory dwelling has an efficient layout with a vaulted ceiling that enhances the sense of space.
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take a look over at:
ecorenovator.com
go to the ground source heat pump page.
lotsa folks there with wealth of knowledge, and willing to share lots of tips, facts, history on actual systems, .
Plus, they will not tell you you are so dumb you need to hire a pro, most there have built their own system with great success.
Folks there will also give advise on how to price and evaluate installers if you are rich enough to afford a $50K system.
dot org
junkhound wrote:
take a look over at:
ecorenovator.com
go to the ground source heat pump page.
lotsa folks there with wealth of knowledge, and willing to share lots of tips, facts, history on actual systems, .
Plus, they will not tell you you are so dumb you need to hire a pro, most there have built their own system with great success.
Folks there will also give advise on how to price and evaluate installers if you are rich enough to afford a $50K system.
Thanks for the link. But might have meant ".org" as .com lead me to a dead page.
http://ecorenovator.org/category/geothermal/
efficient ? or cost effective ?
ground source heat pump systems are very efficient... but they are cost prohibitive and have a shelf life
they require a large capital expenditure that will have to be replaced in the future and will have to be maintained by high cost technicians during their service life
if you spend a fraction of that on insulation and then condition your space with a conventional heat pump system you will have the same compfrot level but a better life-cycle cost.
as my Dad used to say... if you insulate ( and air seal ) your house enough, you can heat heat the house with 9 couples dancing
a good air source heat pump system can heat ... cool... dehumidify... humidify and clean the air
and yes... I have installed ground source heat pump systems in the past
I love it...
MikeSmith wrote:
as my Dad used to say... if you insulate ( and air seal ) your house enough, you can heat heat the house with 9 couples dancing
I love that. When I finished off my attic (about 850sqft) several years after building the house itself, I foamed it. From roof ridge to eaves, and gable end walls. It has no heating. When we get a few people up there, body heat no kidding heats it up.
My house is fairly well built, but for long-term planning I'm contemplating removing my siding and adding 4" of XPS, furring strips, then residing. If I'd only known then what I know now.
I had planned on replacing my oil burner with a GSHP as a part of this "BTU-renovation", but the more I researched GSHPs the more I delayed due the reasons you mentioned.
I really want to keep my hydronic RFH instead of using the existing AC ducts for hot air, I love the RFH and I'm not thrilled with the air movement when we use the AC for summer cooling. There are ways to do that, but for evety question I get answered I seem to come up with two more.
So I'm still looking.
BTW, I read some thread somewhere about you and yours building sailboats a year or three ago. I loved it.
Of course, you left out at least $10K worth of your own time.
As I understand it, a lot of the expense and complexity of the GSHP is in the ground loop. FIrst you need sufficient lawn space for the loop, and the soil has to be suitable for burying it. And if you have to haul in fill that's an extra cost (though there are cases where this fits in nicely with landscape changes being made).
Considerably cheaper is a well-based scheme, but that presumes you have adequate groundwater and that your installation can be made to conform to local health codes (which are justifiably concerned about the potential to contaminate the aquifer).
Thanks for the input everyone.
I'll be building this thing myself so the cost is relatively low.
I'd do solar hot water with the gshp for backup but I don't like the look of the collectors and also I know of a fellow in Germany who heats his house with only solar hot water, (those guys figured out the vaccuum tube thing a while back), but it requires a huge storage tank which I'm also not too keen on the look of.
Plenty of room for the loops so no worries there.
I'll have a look at that site where the experts reside.
Again, if anyone out there knows of a more efficient way to heat a home, I'm all ears.
Tom
'more effiient way'
true geothermal -- but ya gotta live in someplace like Klamath Falls OR, Harrison Hot springs BC, or yellowstone park, or other places where there is ground water > 100F.
Well, the house I'm building is a mile or so from the largest geothermal field in the world but I've heard that true geothermal entails all sorts of problems due to the presence of all sorts of minerals. Equipment doesn't last long.
if U B near geysers, even more 'stuff' in steam since PGE started injecting sewage to increase steam output <G>
professional engineers
DId you consider paying a PE to run calculations?
I did it recently and used professional engineering from Lyon Conklin (my local engineer was Pete, in the Lyon Conklin King of Prussia PA office - he has 30 years experience doing GSHP).
Since I hired him through my HVAC sub, I don't know how they paid them, but I think LC provide the service to win the sale of the equipment, so I suspect it was a pretty cheap or free service.
One warning: I agree with a previous poster that your insulation is far more important, but there are still good reasons to consider it, especially with a straight 30% credit from the federal government. My experience is, however, that the HVAC software models have not kept up with all technology options. I did closed cell foam insulation and two variable speed heat pumps with 9 tons of well. While it is a big house I was doing, I would swear (but can't prove) the system is oversized. The issue is the software models don't properly accont for the foam building envelope (and possibly not the variable speed units either), and therefore tend to size systems as if you had a lot of air leakage.
Since my house is tight, I find it doesn't loose a lot of heat even when we lost power in January for days at a time.
I'm going to educate myself on how to do the calculations. Too be honest, I don't necessarily trust so called "professionals" to do the work as I've seen too many examples of these guys not doing their job. Oversizing of your system could very well be one.
I'm building a house for a fellow right now who owns a place out on a bluff at Big Sur where a ground source heat pump was basically a wasted expenditure due to lack of proper attention on the part of the persons doing the calculations. Seriously undersized.