Groundsource Heat Pump Lemonade?
Out of my Lemon of a well?
We just drilled a 900 foot mostly dry well on some property that we will be building on in the next year. There is water, just not enough to supply – so we will be trying again tomorrow.
Is it feasible to do a GSHP system in a six inch well space?
I have been reading about ground source systems in an effort to reclaim some of my cost. I have a few questions that I hope you all can help me with.
One of the recommended sources from this forum stated that the static water level should be within 150 feet of the surface. Is this just for the economy of pumping the coolant or water down further?
In reference to the above question – could I pump water in to bring the static water level up? My thinking is that this would increase the pressure and push the water back out into the aquifer – yes/no?
Am I understanding correctly that some systems would not take water from the well – since there is very little supply to take from?
Thank you for any information, any recommended links?
Andrew
Replies
900' well? heck why stop now keep going you might hit oil
Can you just hydrofrac your well and get water? (thats what we do here in limestone bedrock)
http://www.goclearwater.com/hydrofacturing.html
I mentioned it to the driller - we had 50' of soil, and the rest has been grey tuff (tuft?), which he said probably wouldn't work due to the clay content?
A closed loop system may work...
A system that takes water out is called "open loop" and a system that doesn't is called "closed loop". I think you really need to get a local installer to come out, take a look, and do some calculations to see about making your well work.
Steve.
>We just drilled a 900 foot mostly dry well on some property that we will be building on in the next year. There is water, just not enough to supply - so we will be trying again tomorrow.
>Is it feasible to do a GSHP system in a six inch well space?
This is exactly what we did, only we were at 805' and <.5 gpm. My installer prefers horizontal to vertical, be/c of ease of repair if necessary, but we had what we had and so we did a vertical. Got 4 ton unit attached to it. Tested performance at closer to 4.5. Very happy with it.
FWIW, obviously the fusing of the HDPE joint at the bottom is critical. And getting all of this tubing to the bottom of the well was a combination of good planning and better luck. It was worthy of a Keystone Kops routine. If you get to the point of doing it, I'll tell the story, be/c it could seriously be the difference be/c this working and not working.
If you put water in the well you'll likely have to clear it with the local health department. You may need to do that anyway, with any form of well-based GSHP.
If you don't put the well to use, be sure to get it legally sealed and have the sealing properly registered, so you don't have to come back later and dig it all up.
Ditto what DanH said.
For open loop systems, some states regulate the return wells rather heavily as "injection wells" because of the potential for groundwater contamination. Since you have a deep, dry boring already, you may have a problem getting a supply well anyway. As other's point out a closed-loop system might make use of the well. You really need to talk to a local contractor familiar with the installation of the systems.
Just out of curiosity, how much money are you folks paying for well drilling. In NC, the magic number seems to be $8 / foot which is putting a serious damper on my interest in a GSHP when I replace my system later this year.
Steve.
Go horizontal rather than vertical. The installers prefer that anyway, given a choice.
Unfortunately my house is in the woods so digging a couple of trenches would be a major PITA. Or I could dig across the small back yard where the septic field is located!!Steve.
I checked into a heat pump and discovered my ground was to dry for it to be cost effective. Might be the same in your case with your drilling a dry hole to 900 ft.
Well, thanks for the info all.
The drillers spent yesterday and today trying to pull 460 feet of pipe and the hammer drill out of the bottom of the hole. A stick of pipe broke where the threaded end is welded to the thin-wall pipe. They sent a tool down to try and grab it, but it just kept splitting the pipe. Once they hooked it, they were nearly maxed out on pull trying to pull it out, and were worried about losing more pipe.
They may be coming back to the well when business slows, to try and retrieve their gear. Today they've moved down the property to try another spot. Hope this one hits - this is getting really expensive.
Around here (Columbia River Gorge, Pacific NW), I think that these guys are average priced - $20/foot first 200', $16/foot after that. You can do the math on a 900' dry hole, every time I do it, my ulcer's ulcer starts bleeding...
That said, our geology is so variable and unpredictable, there is no telling where you will find water. Of our direct neighbors, four are at approx. 150' with great flow, two are >750' with great water, one is 1,000' with a trickle, and two are on springs. I must have drilled through a burial ground or something - that hole seems cursed.
I guess my next question is whether a GSHP is feasible with 460' of pipe in the hole - my guess is no, unless static pressure pushes the water up past it, and I use a closed system.
Wish me luck, they are starting on my next site today.
Andrew
I'm sticking my neck out here, but have you looked around your property for a spring? Where I'm at in CO a spring is a viable option and they aren't that hard to "develop". Will supply the info if your interested.
We have two acres, with a full-on creek running through it, and a large portion which is VERY wet from surface water most of the year. Problem is, we live in a National Sencic Area, and someone at some point in history may have seen a Salmon swimming in the creek... All jokes aside, we are explicitly forbidden from doing anything but noxious weed control within 50' of the creek, which is usually 100', but we got a variance due to the wet-ness of the rest of the property.
Some folks down the hill have an artesian well, which I guess they drilled into at about 60'. Maybe we will get lucky...
A buddy of mine who is building in the area has a spring on his property, but cannot legally take water from it for something like five years, since he MAY be taking water from someone down the creek. We live in a very restricted but very beautiful area. Some folks are dictated where, how high, what color, what screening plantings, etc. they will build, prior to getting thier permits from the Senic Area Mgmt.
AN
I thought you need to have 2 wells for open loop groundsource, one for supply and one for return.
Just an update, we drilled a second well, got 15-20gpm with airtest, at 930feet. The static water level pushed all the way up to 525 feet. The drillers/pump crew put in a single phase, 230v, 3hp Grundfors pump at 750 feet. They told me that it is a 10gpm pump, but I can't find a 3hp 10gpm pump on the Grundfors website.
Will this pump work for me? It was ordered by the guy I am buying the property from, since we had to drill two wells to 900ft to get water, so I certainly don't want to appear ungreatful.
The control box says that it is rated for outdoor use, which I may do temporarily until the house is built. Is this a good idea, or am I asking for trouble?
Thanks,Andrew
From my older Grundfos catalog, model 10S30-37: 3 hp, 14 gpm @325', 9.4 gpm @ 750', 3 3/4" x 57 3/8". This is largest of their "10 gpm" series. Gpm/head are from a chart.
I can't say enough for Grundfos. When in doubt, call them, they're great. My driller supplier sold me 2 wrong pumps before I called Grundfos. They got me straightened out in 2 minutes.
Congratulations on your well.PAHS Designer/Builder- Bury it!
Since I am also in the Columbia Gorge National Scenic Area (in Rowena) and I am planning on a ground source heat pump and I may be needing some well work also, I am interested in where you are located. You might fill in your profile information, also.
We are in the Stevenson area, outside the city limits, inside it's "growth boundary", allowing us some leeway.
We went with M&K Drilling from the Dallesport, and would recommend them to anyone. Gabe Moore drilled our well, and most of the wells in our area - did a great job, and upfront about cost vs. drilling further.
Thanks VA for the Grundfos information.
AN