3Ton Ground Source

Blake.80486 · 04-10-18, 10:40 AM

I don't have the room for a horizontal loop.
So I'm debating between an open loop (well to well).
Or vertical closed loop.

I don't know for sure, but I suspect the area has pretty hard water, so an open loop is high maintenance.

I believe there's about 100' before I hit bedrock.
Normally you'd need 600' of borehole for a 3 ton unit.
I think I'd get better efficiency if I don't use the top 20' (sins the soil will cool so much in the winter). So 80' per bole hole. So 8 holes.

My idea for was to drive 1' black iron pipe down with the end capped off and sealed. The end would have an auger like bit, that should let me wind it in like a screw, and wind it out if I hit a rock.

Once done, insert a 1/2" pipe all the way down, that will give me a feed and return for each.

My reasoning is that 1" iron pipe should have the same conductivity as a plastic pipe loop. A 1" pipe has a circumference of 4"
a 1/2" pipe has a circumference of 2.6"
being metal should make up the difference.

I should be able to do that for $2500

Black iron pipe should last 50 years, the only other option is stainless (any coatings would scrape off). And that would triple the cost.

What do you think?

04-10-18, 10:40 AM	#1
Blake.80486 Lurking Renovator Join Date: Apr 2018 Location: Waterloo, On Posts: 4 Thanks: 0 Thanked 0 Times in 0 Posts	3Ton Ground Source I don't have the room for a horizontal loop. So I'm debating between an open loop (well to well). Or vertical closed loop. I don't know for sure, but I suspect the area has pretty hard water, so an open loop is high maintenance. I believe there's about 100' before I hit bedrock. Normally you'd need 600' of borehole for a 3 ton unit. I think I'd get better efficiency if I don't use the top 20' (sins the soil will cool so much in the winter). So 80' per bole hole. So 8 holes. My idea for was to drive 1' black iron pipe down with the end capped off and sealed. The end would have an auger like bit, that should let me wind it in like a screw, and wind it out if I hit a rock. Once done, insert a 1/2" pipe all the way down, that will give me a feed and return for each. My reasoning is that 1" iron pipe should have the same conductivity as a plastic pipe loop. A 1" pipe has a circumference of 4" a 1/2" pipe has a circumference of 2.6" being metal should make up the difference. I should be able to do that for $2500 Black iron pipe should last 50 years, the only other option is stainless (any coatings would scrape off). And that would triple the cost. What do you think?