Outdoor Wood Furnace Info
All-Purpose OWF Discussions => Plumbing => Topic started by: klingdave on July 16, 2012, 07:09:56 PM
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I'M TRYING TO FIGURE OUT WHAT SIZE PEX TO USE TO RUN 150FT ONE WAY TO A FORCED AIR EXCHANGER.
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Unless you need a lot of heat 1 inch will do the job.
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DO THINK THAT 3/4" PEX IS TOO SMALL OR SHOULD I SPEND THE MONEY AND GO WITH A BIGGER SIZE?
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Yes, 3/4" is too small.
The price isn't that much lower so not even worth considering.
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What is the BTU load you are looking for? Certain Pex sizes can only support so many BTUs, also have to worry about Pump curves
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I would go with 1 1/4 ", not that much more& moves more water.
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You can't get a good answer when we have no idea of btu's needed, pumps being used, incline or not, way to many variables...
It's an extremely rare situation for me as a dealer to have to use anything besides 1"
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Scott7m, what I was trying to elude about the pump was, by going with large pipe you are able to effectively reduce some of the head pressure associated with a smaller PEX pipe; YES you will still have some head pressure associated with any elevation changes.
Also, it does matter what your BTU load is because if you undersize your feedline, your building will not warm up cause it not able to transfer enough energy from the boiler (water jacket) to the building.
In my current installation the smallest feed line I run is 1", cause I go from the boiler (open system) thru a Heat exchanger and out to the garage (4000 sf). When I build the house, I plan on running 1 1/4", so that I add some Snowmelt, THROW AWAY THE SHOVEL AND BUY AN EXTRA SPLITTING MAUL.
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That guy, that's why I said without knowing any of that information it wasnt possible to tell him for sure what he needed.
Are you trying to do all of that on one loop!? Is your boiler protected by a primary and secondary loop?
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I am not trying to run everything on one loop; garage loop is 1", house loop is 1 1/4" & still have room for one more loop off of the boiler. In regards to Primary/Secondary, all the loops from the boiler will be seperated by Heat Exchangers, so that the sytem in the structures is closed loop, while the boiler is open system.
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I am not trying to run everything on one loop; garage loop is 1", house loop is 1 1/4" & still have room for one more loop off of the boiler. In regards to Primary/Secondary, all the loops from the boiler will be seperated by Heat Exchangers, so that the sytem in the structures is closed loop, while the boiler is open system.
That's not what I meant, what do you have to prevent your return water "on any loop" from coming back to the stove below 140? Did you buy a thermovalve?
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A GREATLY understated the complexity of my heating system, but there is a Termostatic valve between the Boiler and the Heat exchanger, also currently there is a very small load on the boiler maybe 50k vs 180k output; that will change in a year or two when the house gets build. Also, I do have a LP boiler (back-up/boost) plumbed in case the boiler is unable to keep up with the system (aka snowmelt runs) or failure; I HATE not having backup plans for heating systems.