I decided to run a few friction loss calcs for this floor and geo loop system I am looking to do.  I would end up with roughly 6000ft of tube in the concrete and probably 3000ft in the geo loop.  I was kind of prepared but still surprised.  The little estimated 1/6hp taco I was looking at might not even touch this job.  If I circulate fluid in the floor, then to the geo loop to pick up heat, the numbers get ridiculous.  Pretty much a 2-3GPM installation here! 

Now, I am looking at pushing fluid through the entire 3000 geo loop continuous but it is pretty obvious that is not ideal from a power perspective.  I was just trying to estimate how long that fluid would be in the field to pick up heat and it is still reasonable at 30GPM.  However, even breaking the circuits open to (2) 1500ft runs in the geo loop, that is still some ridiculous numbers. 

Obviously the concrete tube system would be broken up into circuits for better flow and heat distribution but the geo systel would work best if left in the field as long as possible.   With some basic calcs right now, it appears another ""4HP"" might be required to get the proper flow rates and overcome friction losses. 

What are some flow rates common in geo loops and radiant floor systems?  Am I missing a component in the pump power requirements?  I am figuring on 1" pip in the geo system and rather use 3/4" in the radiant floor simply because it is easier to work with.  I should be able to get my flow rates up with the multiple circuits in the floor.  The geo loop seems a big issue though. 

you are missing a simple aspect.
Shorten your loops & head drops off, pump size will decrease.
If you need 3000 ft geo, look a manifold and #6 500 foot loops,
Same with your in floor, If you are looking at 6,000 feet of 1/2 pex, think zones and 300 foot loops
This is a start point to bring it to reasonable pump size.
3/4 for a radiant is a bear to work with, think 1/2" on residential. 5/8 perhaps but not usually
Dan

I guess my issue there is that water will be in the field for less than a minute and in looking at the conductive properties of the elements involved, it would not much longer than that to really do much good.

It seems I can make the circuits work pretty easy in the floor system but these geo loops really need some thought. Obviously if I made the pipe of the right size to flow a single loop, it would be big girl stuff but at least would stay in the field for several minutes and have an increase is surface area.

I was kind of pondering a remote booster pump in the field but that is probably over thinking it..

wrong,
manifold, header, shorter loops, water is in the field, pump is efficient, systems will work
think geo 1 inch 500 feet, in floor 1/2 300 feet. This is where the concept should begin, fine tune the numbers as you go.
Otherwise your pump will be 3-4 times the cost, and work 10 times as hard.
Dan

What Dan said - you want shorter parallel loops for best efficiency.

Is there a certain target you guys target for a certain size of pipe? Just curious how much head loss you guys are accepting in these systems.