KA-6 Installed in an Out-Building.

Stoker Coal Boilers automatically feed the coal and have controls and pumps just like any conventions boiler. They are intended to be used as a primary heat and often have domestic hot water coils as an added bonus. They can be set up independently or in dual sytem with your existing oil/gas boiler. They can accommodate both hot water base board or steam plumbing.
Bob
Member
Posts: 304
Joined: Sun. Mar. 18, 2007 11:28 am
Stoker Coal Boiler: AHS 130
Coal Size/Type: Pea/Anthracite
Location: Schuylkill County

Post Tue. Jul. 08, 2008 2:53 pm

biggreen1 wrote:I see most installs do not separate the two pipes and let them touch each other. I guess the overall efficiency would not change much. The hot pipe would tend to be a little colder being next to the cold return. But the cold return would be a little bit hotter when it gets back to the boiler so the water will not have to be heated as much. Any thoughts?


I agree with Yanche's comments above. I think a couple of points are worth making however. First, heat transfer between the pipes is a function of the temperature differential between the pipes. I think that typical systems operate with 20 degree heat drop--or at least that is a typical design parameter. The relatively low temperature differential tends to limit the amount of heat transfer. Second, heat transferred to the return line is not "lost". It simple reduces the net transfer from the remote boiler to the home. So long as you are able to get sufficient heat from the remotely located boiler to the home this transfer is of no consequence.

biggreen1
Member
Posts: 173
Joined: Wed. May. 14, 2008 7:39 pm

Post Wed. Jul. 09, 2008 12:03 am

Yanche, Appreciate the response. I ordered 100' of pre made up pipe off ebay today. The pipes are touching like most installation pictures I've seen. The more I think about it I don't think it will affect the efficiency very much because the lost heat from the hot tube isn't really lost if the cold absorbs it and not the ground. The boiler will not have to heat the water as much because it will enter warmer. 100' pex-al-pex insulated in a 4" tube shipped for $575.00. A lot of money buy I couldn't even get pex-al-pex around here for a reasonable price. I may put it in a 6" pipe to make room for more tubing for other wires and to add an additional water barrier.

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biggreen1
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Posts: 173
Joined: Wed. May. 14, 2008 7:39 pm

Post Wed. Jul. 09, 2008 12:08 am

Bob wrote:I agree with Yanche's comments above. I think a couple of points are worth making however. First, heat transfer between the pipes is a function of the temperature differential between the pipes. I think that typical systems operate with 20 degree heat drop--or at least that is a typical design parameter. The relatively low temperature differential tends to limit the amount of heat transfer. Second, heat transferred to the return line is not "lost". It simple reduces the net transfer from the remote boiler to the home. So long as you are able to get sufficient heat from the remotely located boiler to the home this transfer is of no consequence.


I didn't see your post before I made mine. Makes sense to me. Thank you

Rookie
New Member
Posts: 10
Joined: Mon. Jun. 23, 2008 2:38 pm
Stove/Furnace Make: Keystoker
Stove/Furnace Model: KA-6

Post Sat. Jul. 19, 2008 8:15 am

I thank everyone for all the great suggestions. In the final analysis, we will all help to loosten the grip the oil barrons have on us. I will take pictures of my install in hopes that someone else will gain experience from my trials and tribulations.

Ron -
North Brookfield
Massachusetts

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