Hi, I have a proposal for a 4 ton pump with a total of 840 ft of trench, double stacked 1 inch pipe at 6 and 8ft deep, for 3,360 total feet of pipe. The install proposed two trenches. I've attached two images I made with GIS software which show the pipe runs I'm debating. Behind my house is an old gravel pit and I was wondering if I could run one trench 850 ft down the center? My concern is that the elevation drops around 60ft from my house to the end of the 850 ft. Can the system circulate this? If it could, am I going to have higher 'circulating' costs? My other option is to snake it through my backyard. The yard is about 80x220, but I want to leave an area in case I put a pond in some day. Is it ok for the loop to have a lot of curves in it? Will that affect performance or 'circulating' cost? The rear of my lawn elevtion is about 15ft lower than my house. Sorry for the poor image quality, they only allow 100k upload so I had to get creative to get them to fit. Thanks for the input!

Those are jpeg files, not gif. 60ft of uphill is exactly balanced by 60ft of downhill, so no additional circulating cost there. On the other hand, there are advantages to shorter, parallel loops.

Up or down hill, or curves, do not matter for the loop design. As much room as you have, make the trench wider and shorter, put all the pipe in one trench, and keep them 3' apart. One trench, 425ft long, 4 circuits running out there, 3ft apart, 1" pipe, all at 8ft, and then coming back in a second trench, 425 ft long, and you would have a heck of a loop field.

Thanks, just replied to your comment on the other thread. I hadn't thought of that. The contractor said he would do 2 parallel loops 20ft apart. If I'm understanding you correctly, you propose a single trench 425ft long and 9ft wide with 4 parallel pipes 8ft deep (spaced at 0, 3, 6, and 9ft on the width of the trench). Then a second identical trench going back to the house? My yard is only 210 ft across though... Would this design pictured below work? Two, 420 ft loops with two layers of pipe at 6 and 8 ft? Or as I mentioned in my other post, would 3 trenches in the same pattern be better? How far apart do you space the trenches? Contractor said he did 20, but I would think it could be less? Maybe it's for stability of the trench for people and equipment. Thanks again. javascript:amaf_insertHTML('');amaf_toggleInline(4786,28504,0);

That is a lot of 1" loop for a 4 ton. It will certainly get it done. Most contractors do whatever kind of loop they are most familiar with but it really doesn't matter what they do as long as there is enough.

I checked the design against LoopLink and it confirmed the length of trench for a stacked, 4 pipe system. Is this longer than you normally do?

Loop link does pipe generously, but factors include load, depth, diameter, city, soil TC etc. Without all that I'm shooting from the hip.

What I did (and don't recommend) is long loops. Then spliced inside, to make sure leaks were detectable. I'm not a pro.
The reason pros push parallel loops, is splitting your flow down parallel loops reduces fluid velocity in each loop. Reduced velocity results in less pumping resistance.
You can't have too much loop field, but you can have too much loop length. Play around with pumping resistance calculators to see how this works. Bigger pipes, shorter runs, less velocity all reduce pumping resistance, find the balance you are looking for.

"What I did (and don't recommend) is long loops.
The reason pros push parallel loops, is splitting your flow down parallel loops reduces fluid velocity in each loop. Reduced velocity results in less pumping resistance."

Understand there is more than one way to skin this cat. Tubulent flow helps extract btu's with less loop in the ground, but if you have enough loop you can reduce velocity and collect adequate btu's with laminar flow. That would offset much of the pump expense created by extra long loops.