Ontario Pond loop sediment issue

Discussion in 'Maintenance and Troubleshooting' started by Maurice Sabourin, Mar 1, 2016.

  1. Maurice Sabourin

    Maurice Sabourin Newbie but learning quicly...

    I have a simple question...
    Do pond loops fail over time due to sediment buildup, and that they need to be re floated from time to time?


    Thank you
     
  2. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

    I haven't had to (yet).

    But convection is the reason why you can put that much less pipe in a pond and in such a tight configuration. Completely buried, and you would lose that benefit and your entering water temperature would suffer accordingly. You would end up with the equivalent of a short-loopfield in saturated soils conditions.

    Keep in mind, a pond is colder than ground in the winter and warmer than ground in the summer (this is not ideal). So you want to maintain those convection benefits.
     
  3. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    We see ponds to be warmer in the winter than conventional ground loops, due to the convection. However, they also run much WEL384-2013.jpg

    http://welserver.com/WEL0384/

    I have also attached a annual profile of the loop temp for 2013, when we had a "real winter". This year is warmer, the one is not frozen. However, the pond does not store much heat. In addition, it does heat up more in the summer time, and heats up quicker, thus runs less efficient overall in the A/C season. But it never drops below 36F.

    And yes, the loss of convection due to sediment buildup is a concern. It depends how much residual capacity your loop has in comparison to the to total heat extracted or needed by the house. We put the pipes on a subframe of PVC pipes and mount cinder blocks under them before we sink them, so the sediment build up would have a long way to go.
     
  4. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    I do not think that water saturated sediment wold lower heat transfer. The heat is moving through the water not the mud.
     
  5. urthbuoy

    urthbuoy Well-Known Member Industry Professional Forum Leader

    In this case (convection), it is the water itself we want to move.
     
    heatoldhome likes this.
  6. Maurice Sabourin

    Maurice Sabourin Newbie but learning quicly...


    I am starting to wonder if there are many things are wrong with my system, in my other thread about my 5 ton working 24/7 a problem the techs have yet to solve.

    I will try to get some documents form the installers, as to the exact size of the loop, right now the system is working well below what i was expecting.
    Last night I tried to increase the heat to above 70F, to 71F and the system could not do it without kicking the electric aux.

    The outside temperature was around 8f, yes its cold, but a air mass heat pump keeps working in these temperatures... so there is no reason for a GSHP no to be able to, especialy for a pond loop, in a pond that never freeze over completly ... I am suspecting very bad design...
     

    Attached Files:

  7. mrrxtech

    mrrxtech Member

    Maurice,
    With your Pond being spring fed, if the spring water comes to the surface in your pond rather than following a wet weather creek, the amount of sediment collecting should be very small.

    When the identified problems are corrected, antifreeze concentration, low flow and possible low freeon, I believe you'll find your pond is not an issue.
     
  8. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Agreed, right now your pond itself is not the problem. More the way it is piped together, and the size of the pipe going out to the pond. The issue appears to be flow, not heat exchange.
     

Share This Page