how deep should ground loop be?

[yuppie]

I have a trane HP in SE Michigan. First winter in new construction house, and I had to call back the company that installed my HP to check on some issues I am having when temps drop to around 10 deg F. The tech said everything is OK with the unit, and pointed to the incoming water temperature of 31 deg F as the problem. He said they have found out that it takes 2-3 years to let the dirt settle around the pipes in the yard before I will get the max efficiency out of the horizontal ground loop. The loop has been buried for 1 and a half years already. Can I really expect that in another 1 and a half years, the temp of my incoming loop will rise to 45-50 deg.???
(that is what the tech said it should be).

Are they blowing smoke, or is there something to that?

FYI - the loop is 1800 ft long ans is buried 4' underground. Although I am by no means a heating/cooling expert, I questioned the depth before they installed, and they reassured me that this was the standard. I still dont buy that you can bury a pipe 48" where the frost line is 42" and expect the contents in the pipe to stay at 45 deg. This would mean that 6" below frost line rises 13 deg. (32+13=45). I dont think so.

[Ed Imeduc]

Are they blowing smoke, or is there something to that?

Id say for sure. You should be down so you get ground temp about 52o. You would be better off with well water . cant you go to it??? Or look into a DXgeo. you will get heat out of them .


ED my .02 cents :eek:

[yuppie]

The reason they go with the "closed loop" system is because of the high sulfur content in the well water. It is so high that everyone here who does not have city water supply has a sistern, and has the water brought in by truck. THey say the sulfur in the water will corrode the coils prematurely. Another contractor that I had bid the job before I started said the same thing, so I am convinced that the system I have in place is the correct one, I am just not convinced that it was installed deep enough. I was hoping that some readers on this forum could help with info on the standard depth for a
"closed loop" system in my area.

[yuppie]

sorry for the dual reply...but forgot to ask about the "DXgeo" - what is it?

[Ed Imeduc]

DXGeo go to http://www.amgeo.com

It dont use water at all

ED ;)

[GregH]

yuppie,

I can just see the smirk on the face of the one that told you the ground needed to settle.
It sounds as if they are trying to slide you past the warranty.

Ed is right, they should have gone deeper.
Time to do some research on how it is done locally and kick up a big stink before you give up and only have your emergency heat to properly warm you up.

[Garasaki]

Yeah, generally rule of thumb is at least 5 feet under.

The settling story is pure BS.

You probably need at least 40 degree incoming water to do any good. I hope you have some antifreeze in there as you are getting awfully close to freezing (and that's the incoming water!).

One thing you could do to solve your problem is install an electric boiler (this would allow you to keep an all electric system if that is important to you, or put in a gas boiler) and pipe it in as the water comes into your house. However, I think you got hosed by the installers and you should try to get them to pay for it (or reinstall your loop). It would be a simple solution that would work well.

[scottg]

Here is a site that you can go to to find a good contractor in your local area to tell you the truth.

http://www.igshpa.okstate.edu/business_directory/home.html

This site is International Ground Source Heat Pump Association
they are the ones that I went to to learn and get certified.