hot pipes

[electrondady1]

what is required for insulation when trying to transport hot water under ground. perhaps 2" copper with a cold water return. there could  be other lines in the trench, including  1/2"cold water , coaxial cable , a 120v ac , perhaps a 220v ac  and a 2" abs ventalation/vac .

[Chagrin]

PEX plastic tubing is the best choice for applications like this - less expensive, easier to place underground, and much less thermally conductive than copper. For pipe insulation, use the thickest stuff you can find - 2" wall thickness or better and then sleeve this with an outer wrap to prevent water saturation from reducing the insulative properties of the foam. Proper burial depth depends on your location but it's usually around 18" deep.

If you're planning on running electrical it might be smartest to run a high amperage 220V line with a subpanel at the remote location for future flexibility. http://www.selfhelpandmore.com/ is a good place to get the details on this, but you should still consult a local electrician for proper codes for your area. NOTE: If you run copper tubing for water in this trench, you will be forced to buy a four-wire cable (more expensive) for the subpanel. IIRC, 60A aluminum 3-wire cable is $.62 a foot. Copper gets much more expensive. Burial depth varies per code, but it's around 2' deep.

The coaxial cable can be buried at any depth, but try to keep at least 6" of seperation from the electrical cables.

[JW]

Hi Electrondady1,

 Look into Old F's user info, check he's storys, I think there was something there related to this. Last I heard, he was working with a pLc for a outdoor woodstove.

JW

[electrondady1]

thanks guys, i was wondering if that spray foam stuff would work? not the stuff that comes in little cans , but some thing professional insulation companies use?

[Old F]

Well here is what I did for my stove an wiring .

The water lines are 1 inch PEX . The insulation is a two piece  Styrofoam  block  12 inches wide  and about  6 inches thick and came in  4 foot lengths.  

The block had two one inch holes running its length and the water lines are sandwiched  in the middle.

I got this from the stove dealer.  I first  lined the trench with black plastic .

I used  a roll ten feet wide .

I just  unrolled it in the trench and unfolded it enough  to lay the blocks and water lines and folded

It back on top of the blocks. This gave me mutable layers of plastic liner .

And for electric an coax for my ham antennas  I laid two 2 inch PVC conduits in the same trench.

One for the stove electric and one for the coax . I used  conduit  so I could add  or replace things  as needed later.

You mite want to do a search on out door wood stove suppliers  to see what is out there.

Thro it wouldn't  be to hard to home brew the Styrofoam blocks. What kind of stove are you putting in?  

Hope this helps

Old F

To  see my wood stove saga check out my web site.  

[electrondady1]

thanks for the responce old f , i was checking out some of your posts earlyer. just scratched the surface but there was some very handy bits. what i had in mind was an all purpose burner with a water jacket . i'm not interested in steam at this stage.. i will need some control systems   it's a giant corn dog ( one hot water tank inside another)with a door on one end and some pipes  at the other tipped at about a 30-45deg. angle. the door will be about waist high. it will be used to cast and smelt metal from time to time and must consume various fuels as my wood supply gets under control   i will feed the air in under pressure to control combustion. ive collected a lot of the parts. it will be a nice welding project  ive been designing it for about a decade  ought to work ok. i have no cuting torch now and thats slowing me up. if it does nothing but clean up my yard it would be worth the effort. if the prototype works to conduct heat to a building so much the better, i'll build a second one. i want a small hot fire with no smoke  if possible.