I didn't think there could be more than one "happy well driller"   lol!

Eric

Posted By Happywelldriller on 19 Oct 2010 07:47 PM
Adam are you from State College Pa?

Yep- You working on that quote for Boalsburg Doug?

Posted By Dafr on 19 Oct 2010 12:17 AM
Adam, could you explain the process of sonic jetting???

Groundwater Science has a good overview of many well rehabilitation methods that is worth a look at http://www.groundwaterscience.com/free-article-library/well-performance-maintenance-and-rehabilitation/recent-innovations-in-well-rehabilitation/menu-id-134.html

Wanted to post a follow-up to the original post.

We got quotes in for retrofitting to closed loop. Pond loop would be ~$5k, horizontal ground loop about ~$6. So we have some options there and the cost is not as bad as I would have expected.

It still seems like we need to deal appropriately with the iron bacteria issue as it relates to the rest of the plumbing in the house - even if we go to a closed loop, we need to make sure the well and everything else don't have a bunch of issues related to the bacteria....not sure what to do there yet, or what kind of problems the bacteria is likely to cause.

To deal with the iron bacteria for domestic purposes only you may want to look at some type of chlorine injection system or chlorination in the well itself using a "well chlorinator" that sits at the top of your well and drops pelletized chlorine down the well whenever the pump runs. I would only do this if your iron removal system is such that it removes chlorine or you also install an activated carbon filter since it is very hard to control the chlorine concentration.

If iron bacteria wasn't common in your area then a deeper or shallow well with differing redox conditions (reducing or oxidizing environment) and properly sanitized after drilling/pump install may not have any iron bacteria problems and could be another option.

-Adam

Beating a dead horse department...
So, back to the idea of a fallback position of closed loop if open loop fails.

If I were to go ahead with the 550 ft standing column well I've talked to several drillers about for a 5 ton water to water HP, my concern is that the new well may have iron bacteria like my existing well.

If I find an annual coil cleaning is all that is required, that's not a big deal, I can setup for that from the start as several posters have said.

If I have bigger problems using the water and have to switch to a closed loop, how much heating capacity would approx 530 ft X 2 of 1 1/4" loop suspended in the water give me?  Or X 4?  Well will be in granite bedrock that starts at about 8' or less.  Water level is within 20 ' of ground level.

This idea has been tossed around before. Are any of the drillers you are in contact with/or hvac people doing closed loops at that depth in your area? They will be your best source of site specific info.
Bedrock has the best TC for sure and it is definately worth exploring the "worst case fall back position" prior to being their.
Eric

Thanks Eric,

Is it unusual to have a closed loop well 500+ feet deep?  You would have to pump through at least 1000 feet of pipe in one loop.  The other question, thermal contact wise is that well with be naturally full of water.  I know water has better heat transfer than a grout would, also you'd get some movement of water bringing in more heat.  Do these wells have to be grouted?

 

Posted By propaneBeGone on 18 Nov 2010 08:07 AM
Beating a dead horse department...
So, back to the idea of a fallback position of closed loop if open loop fails.

You may want to fully investigate the total cost of correcting the current problem twice (once with a new open loop well and once with closed loop if the new well doesn't work out) as opposed to correcting the current problem once (with closed loop.)  You may also want to factor in cost savings in terms of less maintenance, less hassle, and possibly less service calls over the long haul with closed loop.  It would be interesting to see the actual costs you are quoted.

Putting this another way, if the cost of staying open loop is greater than x% of the cost of just going closed loop, you may just want to go closed loop.  Only you can determine what x% is, but you can get quotes for both fixes to help you make a decision.

thanks Geome, I haven't installed yet, I'm still beating up potential designs - you're thinking of the orig. poster, who may be long gone at this point??

I have been trying to figure out an affordable installation for a while, trying to balance risk of failure against cost. I was attracted to Geo by open loop, fairly inexpensive water well drilling here. I don't have real clean comparable costs but it's something like a $10K+ premium from open loop to (verticle) closed, 5 tons, and reduced peak heating capacity. Open loop is affordable and allows alot of DIY options.

In the end I may have to go closed loop or skip Geo altogether, in my case the ROI is pretty tough with current use which includes a lot of wood pellet stove heat.

Once I feel I fully understand the options I'll get back with the drillers to see how well we can do on costs. You make a good point of course, it seems like pretty much with closed loop, once you get it started up and get the loop purged and as it should be, it just runs and runs without problems for many years - is that the consensus?

thanks for your helpful comments!

Yep, I was thinking of the OP with the iron bacteria problem.

It sounds like many people have open loop, and it can work very well. I have a closed horizontal loop system and can only attest to its performance and reliability to date.

I'm still here!

We've decided to install the closed ground loop. An expensive fix, but not as crazy as I would have expected. The install is in about a week and a half so I'm looking forward to it. We are not sure what impact the iron bacteria is going to have on us even once we switch to closed loop - I guess we will have to see. Nobody around here seems to know much about it except recommending shock chlorination.

Maybe the experts here can give you some advise on how to protect the closed loop from the iron bacteria? I wonder if bringing in non-contaminated water for the loop would help, and shocking the water path through the unit prior to connecting it to the new closed loop would help?

If you use a DSH, could it still get fouled with the iron bacteria? Also, I assume any needed topping off of loop pressure later should not be done with contaminated water?

They are not using our water for the closed loop, they're bringing it in. So that makes me feel a lot better. They mentioned putting a little chlorine into the mix also, to make sure that any residual junk in the unit itself doesn't cause problems going forward - not sure how common that is, but to someone who doesn't know anything, that sounds like a good thing.

Thanks for the response and the suggestions.

Can chlorine be bad for heat exchangers if left in the loop?

Sorry for the terrible pun, but I wanted to close the loop on this issue.

We had our ground loop installed a week ago and except for being six grand poorer, I couldn't be happier. Good timing too because it has since gotten cold in Indiana (and everywhere else). The guy who did the plumbing mentioned that he has never seen an iron bacteria case nearly as bad as ours. This makes me kind of nervous for the future with respect to our well and plumbing - but at least we should have worry-free heat in any case.

Thanks for all the posts - appreciate some expert perspective.

As others have said, you may need to go to continuous chlorine injection + a filter (either in the well or as the water comes out of the well).

Posted By waterpirate on 28 Sep 2010 06:07 AM

A brief note about well driling and aquifers. There is no free lunch. I stopped counting the number of wells that tested clean of iron to start and over time the water quality changed, usually for the worse in regard to the geo. There is also many types of iron present in water. They are all different and require diffferent treatments to cure. In many states the treatment of raw water for re-introduction into the aqufer or enviroment is un-lawfull so check with your authorities.
Eric

I wasn't aware that the water quality can change. I can see if the water was contaminated, like the dumping of toxic materials, but where would the iron come from if the well tested fine to begin with?

A couple of factors are 1) drawing water from the well increases the flow and 2) oxygen can get into the well. Both encourage iron bacteria growth. Note that iron precipitation and iron bacteria are fairly separate issues and it needs to be clear which one is being discussed.

There is a whole feild of science trying right now to answer your question. Solve the riddle and predict outcomes of projects=millionaire. Maybe Adam will chime in with some of the causation, I am just aware of feild results not causes or catalysts.
Eric