Buried pipe choices

[BrownianHeatingTech]

Looking for some feedback on buried piping brands. The pre-insulated and jacketed stuff, of course.

Lost of brands out there, so hopefully some folks have feedback on quality and thermal efficiency on some of them. I've really dealt only with the indoor boilers, but I've had a couple of questions from customers about buried piping lately.

Thanks,
Joe

 

[leaddog]

I went the cheap way. My boiler is 110ft from my house and I've had outside boilers for over 30 years and I've had some good and bad problems with piping. My first setup was with 4in sewer pipewith pvc lines. I ran the lines thru the sewer pipe with spacers taped between the pipe to keep a space. Then I drilled holes in the 4in line and sprayed foam fron the cans inside. Worked untill I OVER FIRED my hassa. melted the pvc, the water leaked and water logged the system.
BAD IDEA.
Next I used 10ft lenghts of 4in sewer pipe and installed copper the same way and that worked untill I found that water worked into the joints and water logged the foam. BAD IDEA
Next I helped my son install his and used 10ft lenghts of 6in sewer pipe. We wrapped his lines (pex) with foil/bubble/foil and slid them into the pipe. His was on a slope so we installed the sewer pipe with the flange downward so water wouldn't be able to flow inside. It has been working for 8yrs now and there isn't any noticeable heat lose.
Next with my eko80 I used 4in flex drain pipe in a solid run. I ran 2, 1-1/4black plastic pipes inside. I then slid my pex inside that. I also ran a pex cold water line in the 4in. I have a dead air space between the pex and 1-1/4 pipe and a dead air space between the 1-1/4 and 4in. I blocked both ends with foam. This seems to work very well.
I talked to a contractor that was selling owbs and this was what he had been useing. He had sold the insulated pipe and he felt that this was very close to the same with ALOT less the cost.
My cost for 110ft run: 4in pipe--- $15 (yard sale find) , 1-1/4 pipe---$35, pex pipe----$200

I may have more heat loss but I can't see it but with the cost difference I can cut a lot of my free wood that I have to cut anyway.

Leaddog

 

[leaddog]

One other thing that I did was put a 1/2 in pex water line in with my run for water to my boiler room. When I run that water It is only slightly warmer than from my house even after setting in 110 ft along side my hot water lines. That tells me that I;m loseing very little heat. I really expected it to be warm after setting there.
Leaddog

 

[Tarmsolo60]

I'm using Wirsbo Ecoflex, I never really looked at the heat loss at both ends but if you look at the way it is constructed it looks like a superior product to me. I was able to barter some labor hours to get a long length of it. mine has 2-1" pipes in it, So I ran 2 runs made one the supply hooking up paralell on both ends and the other length the return, doing the same. I would expect that it must be a very expensive product. I just lucked out and was in the right place at the right time to get it.

 

[Tony H]

I am installing my system now and I got Logstor pipe it's made in denmark I think and it has 2 1" pex pipes incased in a dense foam with a fairly heavy black plastic cover similar to water pipe (4.5 inches total size) . I installed it with my 4 wheeler a logging chain and a 2 ton winch so it seems pretty tough but also pretty pricey at around 12.00 per foot. One buddy of mine has installed several for people using 6" water pipe and pulling insulpipe thru it but said its a tough pull and since has done several with regular pex and just the ends sealed with foam but he cores it 4' to 5' deep. There was also a fellow that said he installs pex and then has a local insulation company come and spray foam all around in a 4 inch layer I think and says it runs around 8 to 10 a foot.
One thing I would try to do is use a full length molded pipe to prevent water migration. After 20 years installing buried cable systems for voice , data and power the schedule type pipes that come in 10 foot lengths do not stay intact over the years here in northern IL with the freeze thaw cycles and while I am not sure how that would impact the pex inside it does not bode well for use with cable systems.

 

[hkobus]

I installed 75 ft of Logstore with 2 1" pex, as discribed above. I believe they have singles and larger sizes aswell. The rigid foam and the outer casing make it very rigid and if you have to go around corners, do it with the coil direction or leave it in the sun to warm a while. If I do it again I will plan better and install it on the hottest day :coolcheese: in the summer, it should be more co-operative :coolhmm:
It is fairly pricey, but will last longer than some of the corrugated products I have looked at, they are essentially drainage tube with incerts. This product is smoth and hard on the outside, more like irrigation tube, will resist mechanical abuse much better. I found this important as I plan to move the boiler in my"future shop" and will have to move the tube as well.

Henk.

 

[TCaldwell]

I tried a little different approach, works very well. Excavated 2ft wide trench3 ft deep, raked bottom smooth ,layed a continous sheet of poly in trench excavation leaving the excess on the lawn on both sides, layed a 2inch thick blueboard insulation chase , ran board 12 inches up on the sides, taped and foamed to seal sides to bottom. bought 2 part ditch foam, sprayed in a 2inch layer bottom and sides. sleeved my 1.25 inch pex supply and return lines in 20ft lengths of 2 inch schedule 40 water line along with other sleeves some for possible future use, layed all in trench, sprayed foam to top of blueboard , layed and sealed blueboard across top of foam and wrapped poly across top, backfilled with excavated dirt. stay above seasonal water table with bottom of trench even if it seems a little high, ground water will rob heat., have over insulated for this reason. my install is in a lawn , temp gauges at both ends show no loss, must be some but very little, good luck tom

 

[heaterman]

Joe, I haven't used any of the traditional types like EcoFlex, InsulSeal, Logstor etc in a long time. Not that they are bad products but we've found a method that works really well for us. We excavate 2-3 feet and lay regular O2 barrier pex in the trench. Our urethane spray foam contractor comes behind us and applies 3-4" all the way around the tubes, whatever size they are. On many job less than 200 ft round trip, we cannot measure any temp drop with no connected load. We finished one last week that has over 600 ft of 2" pex in the ground and the round trip temp drop was 1.4* with a 16GPM flow rate. Do some calling to insulating contractors around your area and I'll bet you'll find one that either dose this or wants to. Cost per foot varies on the amount of actual material they use and the travel distance but it's never been over $10/ft. The 2" job I mentioned was a 65 mile trip for them and i wound up around $8.75 per ft.