Open Loops Geothermal Discharge Noise

Discussion in 'Maintenance and Troubleshooting' started by mwright45, Mar 29, 2009.

  1. mwright45

    mwright45 New Member

    I've had an open loop geothermal for over 2 years now and the discharge is noisy. It comes out of the geothermal unit to a 90 Degree Bend than goes 2 feet out. Than has another 90 Degree upwards about 4 feet than out, right at that bend that goes up 4 feet it makes a lot of noise. So i put 2 45 Degree angles on it right at that point and it made the noise a little bit less i just wondered if other people had the same problem or if they did how they fixed it?

  2. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader


    What you are hearing is the dreaded heat exchanger plug up noise. One can only run "wild and free" water through a DX HX for so long. You have frogs and beaver fuzz in the heat X.

    It is time to clean it.

    I would wait until spring, or three warm days in a row.

    If it is a P/T port system some repiping may be needed.
  3. hardchines

    hardchines Member Forum Leader

    I installed a open loop this past fall and have lots of noise from the discharge water, I used 1/2 inch gate valves for flow control and they generate noise when the water goes through them. My fix was to build a plywood frame with a Plexiglas window on it and mounted this over the pipes and flow meters on the wall, it reduced noise by 75%, so its OK now. Hey Mark.
  4. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    Hey Hard

    What is? Clean your Y strainer, spriing is coming.
  5. mwright45

    mwright45 New Member

    It's always had the noise so I don't think it's cleaning

    the pipe is pvc that comes out of the geothermal

    looks like
    |< 4 Feet PVC heading up
    noise here
  6. MikeandJo

    MikeandJo New Member

    Quiet here.

    Mine has been running for about 3 months now. I was worried about the noise when I was installing it, but it is pretty much silent. You have to be right next to it to hear anything really. 15PSI, 4.5gpm on stage 1 and about 8gpm on stage 2. All plumbed with 1" copper, 2 ball valves to adjust flow and 2 Taco valves. I did insulate them as well to help with the condensation come summertime. If it ever comes at all this year....

  7. mwright45

    mwright45 New Member

    yeah im thinking about going to 1" to fix the problem right now it's 3/4" PVC
  8. Geotech

    Geotech Member


    Do you have a metering device to give you the proper GPM for your unit and what type of solenoid valve do you have, if it is one that snaps closed it could cause you problems since you have PVC connected to our unit, let us know.:)
  9. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader


    Hi and welcome

    Is your unit throttled on the incoming or outgoing side of the unit? I have solved some nasty noises by simply throttling on the opposite side that creates the noise.
    Correct volume of water at a lower pressure via a pressure reducimg valve is also a avenue to investigate.
  10. dancar

    dancar New Member


    late to the thread...
    if cleaning isn't the answer...

    having some hydraulics (fluid power) background, an accumulator or pulsation dampener would reduce the noise. Pulsations in lines are common in fluid power systems and these devices reduce both noise and the pulses. Construct a pvc "bottle" of larger diameter, about twice the size (or larger) of your current line, make it at least a foot long if possible, and insert it into the opposite line where the noise is coming from.
    Looks something like this...
    | |
    | |
    | |=0 <---- pulse accumulator/dampener inline
    | |
    | | <---- loop circuit
    Sounds strange I know, but it works, especially on closed loop circuits.
    Note: a clean out valve or plug would be a great addition.

    Remember, you can always remove it if you believe it doesn't work.
  11. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    Hey WP

    They need you on well over flowing.

    Flow is what this is all about. I might put up with the noise before I starved a unit.
  12. mwright45

    mwright45 New Member

    I'm not sure what solenoid it is, but I know it closes slowly I've listen to it quit a few times to tell. Also my unit it rated for 5.5 gallons a minute soo I don't have a gallon per minute read out on it. I got the pressure on my well set at 60 psi and it makes this noise if I turned it all the way down to 40 psi it don't make any noise at all.

  13. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader


    Without a flow meter or a way to measure the delta p across the coil you are just guessing. Install some ways to monitor your situation and the solution should jump out at you.

    Also I do not advocate starving just regulating the unit to a on the chart number to work with in regard to flow.
  14. MikeandJo

    MikeandJo New Member

    Sounds like a pressure problem mainly to me. You sure don't need 40 PSI running through the HP. My regulator is set at 15 psi. If I run it up to 40, it begins to make noise. I am running through 4 90's before I hit the ball valves. Then 3 more before it's underground and heading out of the house.

    I like the flow meter and ball valves because I can set the flow according to both the book and the delta t.

    There may be no need to change the size of your plumbing at all.

  15. mwright45

    mwright45 New Member

    My Geothermal is hooked up right to my pressure tank which controls all the water to my house so what ever i change the psi to is what the whole house is set to


    I went through this problem in several installs, using different valves, throttling valves before and after the heat pump, messing with pipe sizes, insulation etc. All helped some, but best deal is to install a pressure reducer (about $70) to reduce house or well pressure to 12-15 PSI, then throttle the lower pressure flow. Much less noise.
  17. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    Again, noise reduction is as easy as a division (over several points) of restriction (inlet valve, flowrater, outlet valve etc...). Nice to use a flowmeter (see through gauge) in this application to ensure proper flow. An oversized flow rater helps as well to keep from all the flow reduction taking place there. While you don't need a flowrater at all with throttling valves I still like to employ them to prevent some chucklehead from opening the system full bore and wasting a lot of pump energy (notice I didn't say wasting water).
    Flow raters out side of building envelope (in drain system) also mitigate noise.
  18. teetech

    teetech Member Forum Leader

    As suggested a pressure reducing valve located on the inlet side of the unit will cut your noise.The unit does not care about PSI it only requires proper GPM.

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