700ft to one of my pole buildings to boiler run line or build another boiler

[woodman6666]

Ok guys here's the deal 700ft from a 100x60 pole shed that I am finishing, to my existing large homemade boiler that is in place running and staying there. Tossing around running lines or building another boiler. I sure like the idea of only feeding one fire. But the line expense is scary. It is also uphill. I have done some research and it seems that line size is a must like 2" would help alot and of course a big pump. Looking for opinions and ideas. I am leaning toward running the lines, but I havent found anyone yet who can tell me what pump I need. Open to all ideas, lines, line size, pump size, etc. Obviously would like to go as reasonable as possible. Thanks in advance.

 

[TMFARM 2009]

just me , but 700' is a long run and heat loss would be huge in that amount i think....i dont think you would be as happy, as if you would put another boiler in.. it would be more efficient at least long term.just my opinion.

 

[rancher2]

Not for sure how 700 ft will work but I have 360 ft of one inch running from my 60 by 100 ft pole barn that my Garn sets in. I foamed in the trench the line I have no problem with heat loss or getting enough heat to kept my 100,000 btu air handler happy to heat the house and my house hot water heater.

 

[lfnh]

Pressure drop from run-length + uphill head + freeze up = another boiler, imo.

 

[hanniedog]

Just curious how do you plan to heat the barn? Withe radiant floor heat or water to air heat exchanger. The neighbors put up a new shop probably 100x100 last year and used in floor heat. Really toasty when you walk in, have not had the nerve to ask what the gas bill is.

 

[woodman6666]

Pressure drop from run-length + uphill head + freeze up = another boiler, imo.

I appreciate the info. The little I have learned so far is that the uphill is pretty much offset by the water coming back down the hill (so I have been told) but the pressure drop from the length of line seems to be my largest problem. Freeze up guess Im not sure what you mean as long as boiler is hot and I circulate continuosly how could this happen. Maybe I am missing something here. Again thanks to all for your input.

 

[woodman6666]

Just curious how do you plan to heat the barn? Withe radiant floor heat or water to air heat exchanger. The neighbors put up a new shop probably 100x100 last year and used in floor heat. Really toasty when you walk in, have not had the nerve to ask what the gas bill is.

This one will be water to air exchangers, I have floor heat in main shop and love it this one does not have tubes in the floors so water to air.

 

[TMFARM 2009]

i really dont know. but i would insulate the heck out of the run.. even though its boiling the heat drop from point a to b would be a lot in very cold weather. that would be my real concern.pumps etc can be overcome as well as the rise in elevation.i just wonder the amount of circulation needed would cause issues with the house system... dont know for sure.

 

[lfnh]

I appreciate the info. The little I have learned so far is that the uphill is pretty much offset by the water coming back down the hill (so I have been told) but the pressure drop from the length of line seems to be my largest problem. Freeze up guess Im not sure what you mean as long as boiler is hot and I circulate continuosly how could this happen. Maybe I am missing something here. Again thanks to all for your input.

Freeze up if the pump quits (breaks or power goes off) or if the boiler goes cold.

Don't know what your elevation difference is between barn and boiler, but gravity
systems (full or partial) can and do easily go into a race condition without backflow preventers and flow valves.

Cost of running a sized circ pump all the time maybe something else to consider ?

 

[woodman6666]

Freeze up if the pump quits (breaks or power goes off) or if the boiler goes cold.

Don't know what your elevation difference is between barn and boiler, but gravity
systems (full or partial) can and do easily go into a race condition without backflow preventers and flow valves.

Cost of running a sized circ pump all the time maybe something else to consider ?

Elevation is about 40ft I am guessing that I will have to choke off a little on the return line at the boiler or the water coming down the hill could create a vacum? or maybe I am wrong. Bye the way the boiler is at the bottom of the hill.

 

[TFPace]

woodman6666,
I'm guessing you'll use Bell & Gossett for a pump.

Contact these folks and ask to speak to a sales engineer.Mulcahy Engineered Fluid Handling & HVAC Solutions

This is right up their alley!

Good luck & let us know how this works out.

And yes, you can do this for a lot less than building another one of tiny OWB's



Tom

 

[komatsuvarna]

I dont know anything about these OWBs. As far as pumping water though, You will lose/gain 1 psi for ever 2.31 foot of elevation change. So if its 40 foot of difference there will be 17.31 psi less at the top than the bottom.

 

[komatsuvarna]

Another way to figure it is .433 lbs per foot of elevation. Probably a little easier this way.

 

[lfnh]

Another way to figure it is .433 lbs per foot of elevation. Probably a little easier this way.

So, at 40' rise, static (cold) water psi at boiler would be 40 * .433 ~17psi to make
just atmosphere pressure at barn. Add another 4-7 psi for hot, charged system
and your at 21-24 psi. ASME residential boiler normally have a 30 psi relief valve.
Throw in some friction loss and that relief valve will be a'popping.

Wouldn't even guess is if the boiler can handle the additional supply pipe volume or
the size of the additional expansion tank.

TFPace has the right idea. Phone call.

Interesting question.

 

[rx7145]

I would run the lines. You will need to buy the good line and get a good pump like a B&G PL-36 should work.

The water "running" downhill should help "pull" the water up hill. In any case I don't see that as being a problem.

 

[woodman6666]

Thanks for all the input guys, and yes I was going with a Bell and Gossett pump, my boiler is a non pressurized system with 3400 gallons of water so volume and relief valves are not an issue, I will make some calls this am and see but it sure looks like head pressure from length of line is my biggest hurdle. I will let you know I plan on calling grundfos, taco, Bell and gossett, and the largest central boiler dealer in my state this morning and I will post what they have to tell me.

 

[atlarge54]

700' @ $20/ft is $14,000. Do you think you can properly install the size required for that price, I kinda doubt it. You're looking at over 1/4 mile of tubing before you even include the inside plumbing and HX not to mention the difference in elevation.

It'll be intersting to see what the engineers say. But I'd have to lean toward a separate boiler.

 

[woodman6666]

So far today I have gotten 4 totally different answers.

 

[hanniedog]

So what are the four answers? Yes, no, maybe and I don't know.

 

[John R]

Just for the cost of the pipe, I would think you could build another boiler.
Keep us posted on what you do, you've got my interests peaked.