Any body install a Geo-Thermal field?

[Westonium]

You don't need to be atop any kind of aquifer to put in a horizontal field of tubing to act as the radiator for the geo thermal. PSI/Cinergy may have advocated well-type geo thermal systems in the past, but it is hardly a requirement.

Friends of ours in Plainfield had a vertical geo thermal system, but I doubt they were using the "pump and dump" method. Pump and dump is where they use water once out fo the well, cool or heat the radiator with it, and then dump it into either an empty well (with a lot of capacity), or a pond. Pretty wasteful.

Most geo thermal systems just turn a big section of earth into a giant radiator for the house. I am going to put in the pipes where the dogs will run around so I won't be tempted to plant stuff atop the field, or accidentally dig through it etc.

This is one of the barriers to residential acceptance. Yards are getting smaller, and city folk don't have much call for well-diggers.

Those friends of ours with the vertical geo thermal? They were kidded a bit about it because electricity was quite cheap then. I bet they are the ones laughing now.

 

[Paddy]

If I used a well system, I would dump back into the aquifer. I agree, quite wastefull to fill a creek.

I'm weighing the two options, 1)horz field and 2)wells.
If I go with a hoz field, I can justify buying a BH! If I go with the well system I can use it for house water as well. City water is at the property but on on 'private' system. They want $14,000! to hook on. You can drill a couple wells for that.

Westonium, fill out your profile under "My Home", if you don't mind.

 

[jim_wilson]

Reading this thread has got me thinking about putting in a geothermal system for the garage I hope to build next summer. I plan on a 28' x 40' footprint for the garage and I was wondering if burying the pipes for the geothermal within that footprint would provide enough pipe length to supply the needs for the structure. The reason I think of doing it under the garage is because the location where it is going is on a slope so I am going to have to dig approximately 6 feet down just for the foundation and then backfill inside the foundation to bring it back up to grade for the floor. I could use the BX23 to dig the trenches for the geothermal pipes and get them another 5 - 6 feet down so in total the pipes would be buried probably 10 - 12 feet underground. I am in New England so this will get it well under the frostline. Anybody know where I could find more info on proper sizing for a geothermal field?

 

[Ken_f]

About a month ago I had posted this (below) but since then have put my deposit with a local HVAC company and will have a system installed later this month. A few updates:

They are drilling 3 vertical 100ft holes. They say 100 ft per ton. I have two systems so 6 holes drilled total.

Giving me a nice credit to do all of the outside work with my backhoe. More seat time !!!

The company will not install the poly systems anymore due to the cost of these systems. They are not that efficient with a circulator pump running and the fact that poly pipe does not transfer heat that well. Research on the web shows that some of the high seer heat pump's are not that far away from the loop type systems. (when you figure out the investment payback time)

Not worried about the copper. Its warranted for 20 years and nobody has seen a failure. Also, they install as cathode protection system just incase.

The contactor has installed these systems in townhouse sized yards. All it takes is a 6x6 hole. They have over 80 units now installed in Pennsylvania. One 3000+ sq foot house had a July AC power bill of $15 !! I don't expect that but anything is better than the $250 a month A/C bills that I have seen.

Saw a system running and the compressor is very quiet. Sound level is well below a basement dehumidifier.

Skipped on the free hot water option. Going to go with a on-demand electric when my current hot water heater dies. The system that hooks into the Geo system was just too complicated. I want to keep this very simple.

Will be taking many photos and will keep the list informed.....



------------

Been researching the geothermal systems for some time. Tired of the $3500+ a year that we spend to heat / cool our 3,100 sq ft. house here in SE Pennsylvania. Looked into the water loop system where you would burry around 700 feet of that poly pipe in the ground and pump a glycol / water mix through it. Did not like that as its like running a well pump all of the time on top of a compressor. Then I discovered the DX (Direct Exchange) systems. They drill 14 appx. 50 foot deep holes in a cone pattern from a 4 ft deep 6x6 hole. Then they run the copper tubing down into these holes with a thermal grout. No joints except at the top at the manifold.

You just run the Freon through these lines. No pump... No poly (which does not transfer heat/cold that well) The basement unit is reasonably quiet and does not take up much space.

Estimating that my costs should go to 1000-1200 a year and I get free hot water in the summer.

Its a considerable investment (11K PER SYSTEM) but I don't see LP gas getting cheaper anytime soon and I hate having those outside heat pump units that freeze up every time we get heavy snow / ice storms.

I even have a friend that appealed his property tax appraisal saying that his house did not have central air due to not have outside AC unit. I will definitely try this too...

Ken

 

[Paddy]

google " ground loop geo-thermal. Tons, hehehe, of material

 

[Westonium]

regarding glycol poly
</font><font color="blue" class="small">( Did not like that as its like running a well pump all of the time on top of a compressor.
)</font>
I certainly wouldn't think I'd need a pump THAT large running all the time. I have a 1 1/4" main and its 650' downhill, so I am pretty sure my well pump is massive. Direct exchange sounds pretty intriguing though. I have absolutely no problems with joints in the copper - BRAZED joints can easily be stronger than the pipe itself.

I'll be reading about direct exchange now...
Soldered pipe being buried isn't to code around here anyway /forums/images/graemlins/wink.gif

I still think I prefer the horizontal field concept. I don't know how to make 50 foot deep holes /forums/images/graemlins/confused.gif I can make 3-6 foot deep holes on my lonesome though /forums/images/graemlins/smile.gif

 

[SPIKER]

boy 14 holes 50 foot deep each! thats 700 foot deep of a well! you could hit oil and gas for that then have free HEAT and run the AC using a nat gas unit /forums/images/graemlins/wink.gif also get a PAYBACK lol. ya I know have ot have XX acres per 100 foot of well if drilling for natural gass or oil. anyhow it sounds good, but filling that much tubing with refrigerant sound VERY EXPENSIVE to me if a leak should accure.

MarkM

 

[thehagg501]

I had vertical holes installed by a local contractor. 5 holes 200' each $1000 and change per hole. I was there to see the crew in action. After drilling the holes they sent down 2, 3/4" poly pipes with a fused end and another pipe duct taped to the end to inject bentonite to fill the void all the way back to the top. They left the ends stick out the top and came back later to dig down 7" and fuse the header together and run the loops back to the house. I could have went horizontal and I own a backhoe but from what I have read the vertical holes are more efficient and the sizing is a bit less. That would have been a lot of yard to dig up to horiz. I have a econar 5 ton system and "supplemental hot water" its not free, it will only heat when the furnace runs. I can pull the fuse on the hot water side of the system and the forced air temp will go up 2 degrees. 102F to 104F and back down after replacing the fuse.