Geothermal heat pumps anyone?

[fordmantpw]

Right. So it's all independent on the type

Sort of. From my understanding, they like to oversize geothermal units to ensure efficiency, so they need to push a bit more air than a normal unit.

 

[roadhunter]

Just installed a commercial geo system on a job I was managing. 10 wells 550 ft deep with 11 heat pumps water inside the building, believe the brand is water furnace. Grouted the loops in place. Wells are 20 ft apart and sit under a parking lot. Ended up costing about 300k for the system. Drilling was about 50k but that did not include tearing out the parking lot and replacing it. They just welded tabs on their pipe to bore the hole out a little bigger. They attached pieces of sucker rod to the ends of the loop to help it drop into place easier with the holes being so deep. Ran into several problems as the designers only had 2 lines coming to the building and for some reason that would not allow the lines to purge properly so we ended up going back and installing 4 lines to the building. I believe they said it was "reverse returned" at that point. Interesting to see it all go together but as with most federal projects there was a lot of mistakes in the design that we had to work out in the end.

 

[JamesHW]

We have been considering a water furnace with a horizontal loop system for new construction in the upper Hudson River Valley. We have unlimited land around the site for the loops and excavation should be relatively inexpensive (or DIY) due to the area being all sand. But the sand is also a concern as my understanding of the loop systems is that while wet sand is one of the best environments for transferring energy to and from the loops, dry sand is the worst. My concern is the system would work well during wet seasons and not so well during extended dry seasons. My thinking was maybe positioning garden beds over the loops so that it would take advantage of a sprinkler system. In any event we intend to get some tests conducted to see if it is even viable. What would be great is to find someone with a similar system in the area who has the same geological conditions to us to see how they fared.

The house will be about 500 feet from the road where there is a NG line, so NG is a viable option for the primary heating or a backup to a water furnace.

 

[quickrick]

I am planning on building a post beam home 50 x 104 with the living quarters in half 50 x 52 and the other half being a workshop and garage all with in floor radiant heat. I to want to put in Geothermal and dig down 6-7 feet at which point is clay have 5 acres for this. I assume that the clay would be a great conductor for the geo. My question is I want to heat the garage but not to the temp as the living area just around 45-50 degrees in the winter. How would I determine the size needed? I plan to put down 2 inch blue foam over the 1 foot of gravel base and pour 5 inch of concrete over the in floor radiant tubing.

 

[cre10]

I am planning on building a post beam home 50 x 104 with the living quarters in half 50 x 52 and the other half being a workshop and garage all with in floor radiant heat. I to want to put in Geothermal and dig down 6-7 feet at which point is clay have 5 acres for this. I assume that the clay would be a great conductor for the geo. My question is I want to heat the garage but not to the temp as the living area just around 45-50 degrees in the winter. How would I determine the size needed? I plan to put down 2 inch blue foam over the 1 foot of gravel base and pour 5 inch of concrete over the in floor radiant tubing.

I would go ahead and pour footings and insulate them. Then here is a product called Insultarp I would put under the concrete. I think spray foam insulation is well worth the money. Do a Manual J calculation to determine your heat loss and sizing. A water to water unit with in floor heat would make most sense in the shop area. Then you would have to decide what to do for the living quarters if you want water to water or water to air.