[Vlad]

Originally Posted by AC_Hacker

If you're going down 150 to 200 feet, you are going to need big pipe... 1.5 inch for sure, maybe 2 inch.

I used 3/4 inch, but I wasn't going very deep. In fact, I found that for drilling in sand and for the depth I was going, a shop vacuum worked out better than a mud drill.

* You better calculate how much your 150 to 200 foot drill string is going to weigh, and how you're going to lift it. Even with my small pipe, I had to wrestle it in and out by hand and that wasn't much fun, even at 17 feet.

* I had a reversible electric motor, and it came in really handy when I needed to unscrew sections of pipe. I suppose that since you're doing you're own hydrolic design, you'll put in a reverse control.

Also Vlad, have you done any kind of estimate as to how much heat loss your house will have?

This should tell you how much hydronic piping you'll need.

No less important, it will tell you the minimum amount of borehole you'll need to drill. More borehole is better, but making deep holes into the earth is a lot of work.

Best of luck,

-AC_Hacker

This is why you could not go dipper. With 3/4" pipe you can not have enough water flow to wash out cuttings. In my case I do not know the formation. On top it looks like clay but dipper might be anything. I am preparing for the worst scenario. My stem is 2" (2 3/8 OD) the bit 4". My water pump is 2" with 5 HP electric motor. The gap between stem and wall is less then 1". The water flow will blow all cuttings up.