boiler water line help!

I'll say what my father said to me about this, and he has more knowledge of heat loss, boilers, and pex and all that pertains than probably anyone here. He said the heat loss to the return line isn't a big issue. That heat isn't really lost, it goes back into the boiler. So the return fluid requires less btu's to heat back up. Remember, you can crack a boiler by having too high of a temperature gradient from return lines. We've seen it happen.


Remember, that all of these classic car ntral boilers are pretty inefficient to begin with. A few extra logs burnt year is a small price to pay compared to a broken water jacket on a boiler. Jm2¢

 

If you are loosing 5 degrees in the line to the house and another 5 degrees on the way back to the house times whatever gpm you are pumping that could amount to some serious btu's. If you are loosing 10 degrees into the ground * 12 gallons per minute * 60 minutes * 8.3 BTU's per degree per hour you are talking 60k btu lost just to keeping the ground warm. I'm pulling the 10 degrees and 12gpm numbers out of my butt but if you had that kind of loss you are talking burning an extra cord every 17 days on top of what you are burning to actually heat your house. If you heat for 5 months out of the year that would use an extra 9 cords of wood per year.

 

I agree

I agree that heat transfer from one line to another isn't exactly a heat loss, but when I'm melting a 5 foot path of snow I'm doing more than losing heat between the supply and return.

 

It could be in this thread and I missed it, but did you figure out how many degrees you line is dropping between the boiler and house?

 

Now that's a loss of heat.

 

Hence the reason I'm going to put pipe insulation in rather than nothing

 

Definitely need to start with calculations to determine the heat loss as others have stated. Take that loss and covert it into the corrected Btus ( stove efficiency) and you might flip when you realize how many dollars in wood are going I tot the ground. If funds are an issue, I suggest digging a few test pits to locate the line by hand. If you think you canattack it by hand, a less costly temp fix is to open a trench a foot or two wide and lay strips of two inch foil backed insulation directly on the pipe. You don't need to cut ot sleeve anything and your heating system stays on. It's a ton of digging and some minor expense in insulation, but I bet will mitigate some of the issue. I have done this on natural gas condensation lines that were freezing and for a variety of reason could not be excavated or buried deeper. Tough situation..... Good luck

 

Great forum...I just found it and was checking out this post. Years ago I had to dig up My underground line and add a second set of lines. I checked out a product called Dri Therm which was a powder type material that is poured around the lines to form a waterproof and insulated barrier. I had a 175' trench and didn't use it but I swore if I was ever going to do it again, I would use it. Just a thought. Dritherm International Inc.

 

Shaggy, we had to do the same thing with our cold water well pipe many Moons (18+ yrs) ago, when we found out the pipe was less than 12" from the ground in some places.. Dug a 1 foot trench on either side, dropped in 4" of styrofoam (Blue board) insulation underneath, wrapped the pipe in foil-backed insulation, placed a small strip (2" x 1") of Blue board on either side, then 4" of Blue board on top to create a 'box' channel around, to fully insulate the pipe.

This largely solved our issue, although we still keep the bathroom sink running on very cold spells (0F and below) of weather during the winter months, which was pretty much every day last winter.

This was the least costly option, out of all investigated / considered, but is a lot of work if you DIY, no question.

Thought you might like the info & option. ( If you are considering doing this, I would try it on a section of pipe during the winter months to make sure it works for you, then you can to the entire line when the weather breaks / during the summer months. )

 

Soon as I get the cash time and ambition I'll be replacing it with some real good line, that is if I keep heating with the owb.

 

Dig er up in the summer
Get on the saw and burn the wood
No sense takin her off line unless your buyin wood cost is more .
All lines bleed heat a bit
I'd be more worried oxygen gettin in your water oxidation
I used logistor lines and insulated the trench , running 100 feet or so 3 feet deep , in same trench is a cold water feed to my shop , it will run luke warm when I turn it on tellin me my trench is warm, so I'd say the heat loss would have to be a few degrees from one end to the other.