We had a waterfurnace system installed in our cabin several years back. We use water from a well, which eventually drains back into the river. We have been happy with our system except for one issue which the waterfurnace people don't seem to know what to do with...or wont. The exit noise of the water going from the waterfurnace to the underground pipe is excessive. It sounds like screeching sometimes, with varying degrees of noise. Sometimes it runs quieter. Its enough to wake you up from sleep at night, and the furnace is in the basement. We wonder if it is a bad valve upon exiting the house, or maybe improper pressure, or maybe even that the exit pipe is the wrong type. The waterfurnace folks tried piling on a bunch of insulation over the pipes to quiet them, which greatly dissappointed us. As if that were the answer to our problem. Otherwise, our cabin is small and well insulated and sealed up and its great to have a heat source in the winter when its alll snowed in and we go up to visit a warm cabin! Any suggestions out there on the source of our water noise or a solution???

Angie,

Your open loop piping should look something like the attached JPEG image.
It sounds as if you are getting turbulence noise. The Flow Regulator restricts the water flow, giving you the correct water flow needed by the heat pump. As water passes through the regulator it leaves air pockets in the water stream thus becoming turbulent. If your piping is set up correctly, the down stream ball valve MIGHT** be able to be closed down a little bit. Doing this puts a little back pressure on the regulator, filling the pipe with water and not allowing air pockets.

** Flow regulators are rated for a set amount of GPM. If your unit needs eight GPM and the regulator is rated for eight GPM , you can not close down the ball valve without reducing the flow below the required amount. We "up-size" our regulators, this allows us to close down the ball valve while retaining the correct flow and making the system quiet.

The only way to tell if you can close down the ball valve is by the pressure drop through the heat exchanger. As the valve is closed, keep checking the pressure drop. If the system quiets down AND you still have the proper pressure drop, you're good to go. However, this may be best suited for your contractor.

Bergy

I had a similar problem with a console unit .... I used PEX on the line leaving the unit but used a foot of copper on each side of the solenoid to hang it..... That small length of copper pipe was radiating the noise into the framing.... I changed my pipe hangers to three times the pipe size so I could isolate the solenoid piping with pipe insulation and changed the flow slightly .... I also cut a piece of 2 inch styrofoam the size of the unit, painted it black , and set the unit on it..... Now it is a quite as a church mouse ....... Dave in NH

I have had a great amount of success by throttling on the incoming vs. the out going. Installing pressure reducing valve, inspecting existing orifices for pipe burrs or other debris. Increasing the size of the exiting pipe to reduce velocity in the pipe inside the house. I have never been successfull trying to insulate the noise from the house. It actually made it worse in one case.
Hope this helps
eric sackett
weberwelldrilling.com

No personal experience in this, but if you still have a problem after verifying pressure and flow, you may want to put a u-bend and burp valve or air bleed in the discharge line outside the house. That would ensure the discharge line in the basement is fully flooded, reducing noise.

I agree with waterpirate. The pressure reducing valve (PRV) on the inlet water line has been huge for us (open loops very popular here in Idaho). Every plumbing job / well pump combination is different. We went away from the PRV for awhile, and had no problems. Then, on two systems in a row, terrible noise. Installing the PRV made a huge difference. In some cases the PRV is reducing the pressure all the way down from 60PSI well press., to whatever pressure results in required flow rate. So, even this valve, can make a small amount of noise, but applying just a little back-pressure (as noted above) quiets it right back down. I think we use an adjustable Honeywell PRV, 1" with single union adapter.

Have you received any good advice.  I have the same problem with my water furnace as well. We don't use a well for the water we have under ground/water coils.  The people that installed the furance say they need to put a time release pressure value on the furnace, but can't get approval from water furnance that it won't void the warrenty.