Geothermal Loop

[[XC] Synthetickiller]

I'm in the process of having a house built & I'm going with a geothermal loop. I had a quick discussion with the guy in charge of installing the HVAC unit & he said hooking up in inlet & outlet from the unit should be no problem. He said in the summer, the water should be 80F, but will dip between 50F and 60F in the winter. I'm in southern Louisiana, so that explains that not so extreme winter temps.

I'm concerned about a few things.


Is 50F too much of a delta if the air temp is about 70F?

The water pressure in the loop is 30 PSI. would that be an issue running MCP 655 off of a Koolance RP-452x2? He can't adjust the pressure as it's ideal for making the loop run properly.

What do you guys think? Anything I need to know about the loop I didn't bring up?

[OldChap]

A couple of thoughts from me

My knowledge relates to research done for a heat pump here in UK

Those summer/winter temperature figures surprise me as I would expect ground temps at 6-10 ft deep to fluctuate less seasonally when the heat load going in is somewhat constant.

If you are thinking of connecting to the same loop as your air-con then I understand where he is getting those figures... I am not sure that is such a great idea as you would effectively be cooling with warmer water produced by your hvac.... unless of course you can oversize that loop. However, the pressure issue could be overcome by using a plate heat exchanger thereby allowing you to run your rig-side loop at whatever flow/pressure you wish.

Personally, I would dig for a second geo loop at the same time as I had the machine digging the hvac system I think.

[NKrader]

Personally, I would dig for a second geo loop at the same time as I had the machine digging the hvac system I think.

Same here

[[XC] Synthetickiller]

Yep, I'd be tying into the loop. It should be able to handle 6 to 7 tons of cooling for the house, so throwing a PC or 2 into that configuration shouldn't be a problem.

Basically the cooler side will bring water to the WC'ing loop & the outlet from the rig will feed into the "hot" portion that enters into the ground loop to get rid of the heat.


I could also simply just run tubing at the same time that would only connect to the PCs & just use the ground as a rad. That would be much more expensive.