Lake loop froze and floated to surface

Discussion in 'General Discussions' started by Waukman, Aug 3, 2008.

  1. Waukman

    Waukman Member

    Number of forums...

    I am wondering if there are too many forums currently available on this site. While it may seem appropriate so many have no posts at all. Another problem is that many posters don't really pay attention to which forum there are using and as a result threads get started in the wrong place.

    One idea would be to eliminate the individual state forums and have one forum for US end users and US Vendors. This would give a seperation of end user questions and those that are specific to folks in the industry.

    What do others think?
     
  2. Chuck

    Chuck New Member

    I think it would be a very good idea if the forum provided threads specific for geo industry folks, and threads for end users. I agree there are too many sections, many of which see very little traffic.
     
  3. Guest

    Guest Guest

    agreed, the individual state forums seem unnecessary. there is a benefit to having everyone use the same forum, since questions get asked once and answered once. I can foresee the same question getting asked 50 times, one in each state.
     
  4. We will be adding a "Professional Only" area soon.

    The individual state forums are in place for the planned editions to GeoExchange.org. Each state will have it's own subsite, ie; utah.geoexchange.org that is reachable with utahgeoexchange.org

    The idea is to provide sites tailored to individual states and municipalities. The state forums will support discussions relevant to a specific region not general geo questions.
     
  5. Chuck

    Chuck New Member

    That sounds great.

    We have recently launched a new geothermal marketing, financing and engineering company. I would like to post a thread introducing ourselves, are there rules or restrictions relative to posting such notices?
     
  6. HOLYSTANSAUER

    HOLYSTANSAUER New Member

    I have a new 1600 sf home in central Illinois on a 14 foot deep 200 acre lake using 4 tons of geothermal heat. The manufacturer told me to insulate my basement to make the system work better. When the project ran over budget, we eliminated the basement insulation. The basement is mostly for storage so we don't need to heat it.
    The lake loop was running at around 20 degrees causing ice to encapsulate the loops and lift them to the surface where they are now hovering below the ice. The manufacturer is implying that had I insulated the basement, this wouldn't have happened. In the meantime, my system shut down due to the loops being too cold. I am now on full time electric backup heat= $$$$$$$ electric bill.
    It seems to me that by eliminating the insulation, I could expect a higher electric bill. Instead I have more or less total system failure. Could not insulating the basement make that big a difference? Is this situation really my fault?
     
  7. teetech

    teetech Member Forum Leader

    Seems like you were right.
    That's possible, not a lot of information to go by.

    Out of curiosity was the unit running during construction?
     
  8. HOLYSTANSAUER

    HOLYSTANSAUER New Member

    The house was modular, it was complete when the unit was installed. I offered our contractor $2000 today to install deep wells instead. He told me he'll never do a lake system again. He has two of them and they both failed.
     
  9. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

    Don't give up.

    Lake loop systems can and do work great. Post some of your design spec's and we can probably point you in the right direction.
     
  10. engineer

    engineer Well-Known Member Industry Professional Forum Leader

    $2k doesn't buy very much deep well in most places.

    Lake loops shouldn't have floated.

    What is the total length of the loop piping in the lake?

    A Manual J building load calc would provide the additional heat load attributable to the uninsulated basement.

    I haven't done a lake loop, but my guess is that it is expected in the course of winter operation that lake water will freeze around the tubes. I would expect the design to allow for this - clear ice has a reasonably high conductivity. I would also have expected that the installation would have allowed for this by weighting or otherwise securing the loops to the bottom
     
  11. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

    We've done a few lake loops and yes, you need enough weight to deal with future ice formation. Unless, your lake is warm enough in the middle of winter.
     
  12. teetech

    teetech Member Forum Leader

    A 20F loop is going to make a lot of ice. No wonder it floated. I'm surprised it could stay running at that temperature.
     
  13. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    The loops where not deep enough

    That's is why they floated. I would also venture a guess that they were not properly weighted. A pond stratifies and warm enough water is available in the depths. The pond in Valley City, Ohio provides 43*F loop entering water temps at -15* and a 12 inch thick covering of ice.
     
  14. HOLYSTANSAUER

    HOLYSTANSAUER New Member

    Thanks for all the replies. I am very happy with my HVAC contractor in spite of the problems. I don't know the loop lengths other than he said there was one loop per ton of cooling for a total of four loops. He said the spec called for two concrete blocks per loop. We could see 8 blocks under the ice so the installation was per specifications. The system failure appears to have happened because of many stresses to the system simultaneously.
    1. The outdoor temp went from mid 30's to 5 degrees over the course of a day or two.
    2. The cold was ushered in by some very high winds that super cooled the surface water.
    3. The lake temperature at 16 feet deep was 34 degrees one week later.
    4. The house has no wind break.
    5. The house is 15 feet wide and 2 stories tall. It has many windows, bat insulation and very few interior walls.
     
  15. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    A way to fix the problem

    I would find out the loop size and length, before trying this fix.

    We used 280ft of 5/8 inch tubing per ton in Valley City. The loops are from about three feet to 12 feet deep depending on where one measures. The loops attach to an adjustable 1 inch manifold and the 1" pipe runs 150' each way to the pump. We are pushing 4 GPM per ton to the loop field or 12 GPM total.

    If the sizing is correct, one could lay a blanket of chain link fence on the ice over the loop field and weight it down with as much broken concrete as possible. I would tie the concrete to the fencing with stainless wire. I would also tie the fence together so that it acts like a unit. Then wait for a thaw.

    Please feel free to contact me if you need further help. I do not have the link on this machine, but there is a great explanation of how pond loops done by the University of Indiana and McQuay.
     
  16. teetech

    teetech Member Forum Leader

    The numbers given for the lake and the pond are miles apart. Something just doesn't add up here.
     
  17. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    I agree

    with teetech. The numbers are not correct.
     
  18. codfather

    codfather New Member

    I'm sorry, but I don't believe this.

    It couldn't be more simple. If you have a sufficient amount of tubing in the lake, with an acceptable antifreeze solution <ie: 20% methanol or 25% ethanol>, then NO freezing around the lake loop would/can occur, assuming that it's a lake, and not a small backyard pond. If you have freezing around the piping at ALL, then the lake loop, circ pump size or antifreeze level has been miscalculated, PERIOD. This is ABC Geothermal, and your situation is a joke. Tell your installer to go back to school. My company has been installing lake/river/ocean loops for 30 years. This is a badly designed system. If I had to guess, the most common rookie mistake in this type of application is "short-looping", meaning not enough piping or pumping power. Check it out.
     
  19. purgerite1

    purgerite1 New Member

    You could also have everything designed and installed correctly but not purged properly. Air or debris in the lines could cause loop lock - no flow... Ask your installer what was used to purge his systems and to very his flow rates and velocities....
     
  20. HOLYSTANSAUER

    HOLYSTANSAUER New Member

    I'm not sure what you mean the numbers don't add up or the comment about not believing this. Do you need pictures of the loops you can see frozen into the surface ice? The HVAC contractor hired a thermal imaging guy to analyze my house. He found the house to be tighter than average but that more than half of my return air was being sucked from the basement. The thermal imaging guy said he found no fatal flaws in the house itself. The HVAC contractor maintains that due to the basement not being insulated and because of the return air problem, the furnace run times were much too long. He said the run times made the fluid in the loops get too cold causing the ice to form around them. I maintain the loops would also freeze if the door was left open all day. Since that situation could happen in any home, the loops should be sufficiently weighted to prevent that catastrophy.
     

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