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bassman

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I have my boiler set between the house and the greenhouse and there is 130 feet of line from the house to boiler and 125 to the greenhouse .
I am getting a temp of 185 supply and 181 return at the greenhouse and 185 supply and 180 return at the house .
this is taken with no exchangers running .
what are you guys seeing ???

shayne
 
i don't have an OWB, but i have baseboard heat. you only lose 5 degrees making a run thru the house? is your house warm?
 
Those are pretty long runs, and that is a very good reading on your temps. Tell us more about your install, using PEX? Insulated? How Deep? Brand of OWB? Are you getting ready to install some exchangers? How are you heating your house, forced air furnace, radiant, etc.?

Basically that looks real good, my run is about 100' and I drop at least 10 - 15 degrees, reading with an IR handheld surface thermometer.



I have my boiler set between the house and the greenhouse and there is 130 feet of line from the house to boiler and 125 to the greenhouse .
I am getting a temp of 185 supply and 181 return at the greenhouse and 185 supply and 180 return at the house .
this is taken with no exchangers running .
what are you guys seeing ???

shayne
 
iCreek that sounds a little excessive to me. I am losing about 5-6 degrees over a 175' run, and thats AFTER my water goes through my hot water setup. Also the last 20 feet or so under my house isnt even insulated.

My run to my barn is only 25' and I dont have a gauge in there.
 
That is the temp reading after going through my water to water exchanger, where the cold goes in around 40 - 50 degrees, then I go out to my water to air exchanger... I have not measured my first hot input....

Got me thinking I need to now !! : )

Huskyman, what are your temps at your heat registers? Assuming you are forced air?


iCreek that sounds a little excessive to me. I am losing about 5-6 degrees over a 175' run, and thats AFTER my water goes through my hot water setup. Also the last 20 feet or so under my house isnt even insulated.

My run to my barn is only 25' and I dont have a gauge in there.
 
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I am not sure of my temps

But I would like to see a delta T of 15 to 20 degrees. Might as well leave the water in the heat exchanger long enough for it to dump a little heat.
 
Huskyman, what are your temps at your heat registers? Assuming you are forced air?
Sorry I dont have a way to measure that. I have baseboard hot water heat so it should be within a couple degrees of my temp reading at the exchanger. Now that I think about it though, you are probably ok. By reading the surface temp with an IR gun you are going to get lower readings than if you had a gauge with a probe right in the pipe.
 
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On the 160ft (320ft round trip) run to the house, usually 4 or 5 degree drop with nothing drawing. From the stove to where the pipe enters the house before going thru exchangers 0 to 1 degree drop.
 
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I loose about a degree for every 15 feet of underground.

Holy cow, if your run is 90ft your loosing 6 deg.....thats about 6000 BTU's

I would say 1 deg per 125 to 150 is what I see is a good amount.
 
Mine is run 190 feet and have a guage in the basement where it comes into the house and when its 180 degrees at the OWB, its 180 degrees where it comes into basement, Separeted my lines, there not touching, and insulated them and shrink rap them, and ran them trough a 4 inch tile...works great...
 
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