Trench for thermopex

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jimde

New Member
May 27, 2009
71
Northeast WI
I picked up my 1.25" thermopex today. 150' from shop with solo 60 to home. My question is what needs to be run in the trench with the thermopex. Do I need th run undergroung wire? I also have read about people running a 3 or 4 inch drain tile for future use,but I am not sure what this would be for. Also do I have to dig below the frost line or would 2 feet be sufficient?
 
Below frost line, if you bury wire which I did make sure it is rated for direct burial and don't forget to add the up and down portion of the trench for your measurements along with the length.

Gary
 
I just finished a short run and put in a 4" PVC drain pipe (no holes). It took about a week and I was running an extra power line down that pipe. It was a lot easier to have it then to dig a new trench. A good move is to leave a rope in the pipe so that you are ready to pull what you need. The larger size is there so I can run another Pex run.


You could put a locater wire in the trench (they are normally yellow) and that will help folks find the run.

Digging below the frost line is the common practice, it protects what is buried from frost heave, which is a mechanical movement and or distortion.

I am sure folks will have lot of other stuff you can put in your trench, such as: data lines, power lines (copper is pretty good right now), and even phone lines or a line to control remote valves and the like.

good luck
 
jimde said:
I picked up my 1.25" thermopex today. 150' from shop with solo 60 to home. My question is what needs to be run in the trench with the thermopex. Do I need th run undergroung wire? I also have read about people running a 3 or 4 inch drain tile for future use,but I am not sure what this would be for. Also do I have to dig below the frost line or would 2 feet be sufficient?

Below the frost line is best for all sorts of reasons...

What is your arrangement for power? I assume you already have power at the shop, if not it wouldn't be a bad idea to drop a conduit in for a power line. Definitely put in a 3/4 or 1" conduit or two for data and control lines - you can direct bury appropriately rated Cat 5 or other signal wire, but it is hard to repair / replace it in the future if needed, and the direct burial grade stuff is hard to find. If it's in conduit, it is no problem to add more lines, or replace as needed... It can be very helpful to have good signaling capability between the house and shop, as it makes it easier to do remote monitoring / control from either end... Definitely leave a "pull string" in the conduit - what I've used is nylon mason's twine, cut about twice the length of the conduit plus a few feet. Tie each end to something permanent, and bundle up the extra and leave it in the box - if you need to do a pull, fasten the bundle in the middle of the string and use it as a shuttle...

Not sure what the drain tile would be for, unless someone was thinking in terms of being able to pull additional Pex loops later, and I don't know how well that would work...

I would also bury a length of yellow caution tape a foot or so above the piping, and again say 5-6" below the surface - in case some future backhoe enthusiast forgets where the pipes are, this can give a warning to not dig deeper by machine...

Gooserider
 
Thanks for the imput boyz,but could someone explain the data and control lines. If my storage tanks are in the outbuilding with the boiler will I be able to monitor tank temp? Would this be considered data lines. I have enough 2 inch PVC to lay parallel to the thermopex. I will have to core a additional hole through the basement wall for the pvc. Will the 2 inch line be sufficient for my electrical needs. The power is already in the shop.
 
jimde said:
Thanks for the imput boyz,but could someone explain the data and control lines. If my storage tanks are in the outbuilding with the boiler will I be able to monitor tank temp? Would this be considered data lines. I have enough 2 inch PVC to lay parallel to the thermopex. I will have to core a additional hole through the basement wall for the pvc. Will the 2 inch line be sufficient for my electrical needs. The power is already in the shop.

If you have the right hardware, you can monitor anything and everything that you like. 2" PVC should be all you'd ever need for data and control stuff. The only big item is that you can NOT run power in the same conduit, but since you have power in the shop already, that shouldn't be an issue.

Data and control is pretty much anything in the way of low voltage signal stuff, and doesn't have to involve all that many wires depending on how it's done. Probably the easiest way to define it would be to say it's anything you could send over an ethernet cable or a phone line... The ideal is to have a computerized system, like the NoFo control system, in which case you could, at least in theory do everything over one run of Cat5 ethernet cable... If you wanted to do discrete signals for everything, then you'd need more wires...

Gooserider
 
Thanks Gooserider, Is there a specific name brand or place to purchase this data and control wire that you are aware of. My plan is that once my trench is dug and the thermopex installed I will install the 2 inch pvc with the wiring needed. As I push the wire through I will have the mason line you spoke of tied to it. This way my wiring will be in with potential for pulling more.
 
jimde said:
Thanks Gooserider, Is there a specific name brand or place to purchase this data and control wire that you are aware of. My plan is that once my trench is dug and the thermopex installed I will install the 2 inch pvc with the wiring needed. As I push the wire through I will have the mason line you spoke of tied to it. This way my wiring will be in with potential for pulling more.

Cat 5 or higher( cat 5e, cat 6) ethernet data cable should be fine for most systems, available at places like Home Depot and Lowes. There are many ways to pull the cable but
rather than use a fish tape or try to push a string through each length of pipe as you glue it together a vacuum or leaf blower to suck/blow the pull string through works well.
You just need something that fits loosely in the pipe, paper cup, ping pong ball, big gulp cup for the larger pipes, and tie the pull string to it. Amazing how fast a 200 cfm
compressor and a big gulp cup will send a line through an 8 inch sewer line!

An extra line 2x the length of the run is a good idea for future pulls.
 
i bureds mine two feet down. I then added a layer of 2 inch blueboard. That is equilvent to 12 inches of soil. I have 85 feet of run. I haven't noticed any temp. drops
 
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