Heat Loss From Out Building and Buried Pex

I still have issue with the wet insulation around the pex. It is a major problem.

Rob R. wrote:If the pex lines are uninsulated in a single piece of PVC, won't the heat try to transfer from the supply to return? Not sure how much...depends how tight the lines are to one another.

My send and return to my hot tub are in a single PVC pipe. It's a very tight too.

Seems to work out for what ever reason lol. No idea if they were separated if it would make a difference. The heat has to get there, otherwise the loop would boil, wouldn't it?

windyhill4.2 wrote:Sorry,i was not trying to beat on him,only trying to clarify a few things.My key board does not have the alphabet in order so typing goes slow for me,besides,repetition is often the only way to get thru my thick skull or slow functioning brain. Rob R. is it really critical if the pipe temps are similar IF you have hot enough water for needed heat ? at least the water going back to boiler is not cold in that scenario.

If it heats the house, then no, it doesn't matter. I don't know how much of an issue it is anyway, just mentioned it. It is generally preferred to insulate each pipe separately.

WOW, Scottscoaled, that is a very distinct melt line,i saw your pic.& looked outside where my pex line is ,i know where it is because I put it ther but if you were to look you would have no idea,snow cover is the same ! Rob R. some are very adamant about separation of the 2 pipes,we do have some insulation between ours.

never thought about the return getting warmer going back to the boiler good point, 3 inch pvc with two 1 inch pex lines inside...have never had any snow melt on top of where my line is WOW! and your set on it being wet insulation and not the fact its only 2 1/2 ft below the surface???

My lyme riddled brain works a bit slow at times & dchartt your reply does point out a downside to sending the water temp back at similar temp it left the boiler. If water temp is too little change that would prevent the boiler coming on until all the water temp is low ,causing more of the wide swings of up & down cycling.

Do you actually think though that the return is rising in temp that much in the amount of time it travels 140 ft? I honestly don't see it I think thats a bit far fetched, how did your grandpop say it freetown fred?
What about my return cooling down my supply? Im not buying it

see if you can buy or even borrow a infered thermoter and check the return and supply lines(both) from the boiler to the house boiler and both lines from the house boiler to the outside boiler.What i'm infering is don't just read them at the outside boiler,you will get a better understanding of heat loss of the lines only.

Ill bring one home from work and see what the temps are
Would the heat loss in taking the water to my house be evened out by the heat increase going back to the boiler? Its getting too technical!

how many of you guys running these coalguns remove the fan assembly during the season to clean out the air chamber that leads to on top of your fire? reason Im asking is because mine was half full of crap when I had mine tore apart yesterday and its definitely something I will be doing from now on during the winter

dchartt wrote:how many of you guys running these coalguns remove the fan assembly during the season to clean out the air chamber that leads to on top of your fire? reason Im asking is because mine was half full of crap when I had mine tore apart yesterday and its definitely something I will be doing from now on during the winter

Wish you had a picture of that...pictures is worth a 1000 words.

How did you insulate the outside of the sch 40 pipe?
How was that insulation then protected from the earth pressure/weight being at 4-1/2' buried depth?

Not so sure you would have a visible snow melt line showing due to pex being so deep buried.

McGiever wrote:How did you insulate the outside of the sch 40 pipe?
How was that insulation then protected from the earth pressure/weight being at 4-1/2' buried depth?

Not so sure you would have a visible snow melt line showing due to pex being so deep buried.

what type of insulatoin did you use,fiberglass,open/closed cell.?

closed cell pipe insulation, my theory was the deeper I buried it the more insulation the earth itself would provide, didnt make sense to bury it within the frost line

Lightning wrote:Rob R. wrote:If the pex lines are uninsulated in a single piece of PVC, won't the heat try to transfer from the supply to return? Not sure how much...depends how tight the lines are to one another.

Two pex lines in a single pvc conduit would exibit little exchange , UNLESS said conduit wasnt glued together to above ground levels. If not you would have a water filled conduit and a great heat exchanger. Same goes for a gravel /sand filled trench in clay (non draining)soils