Two indoor boilers plumbed together.

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Rick18

New Member
Jan 10, 2018
12
NH
I have two tasso wood boilers Plumbed together in my shop feeding the oil boiler in the basement. I have never seen or heard of this being done since I did this. Its been a long project but the outcome is incredible, the oil boiler never comes on even a below 0 temps. I'm looking for advice to improve this system and to ask if anyone has ever done this?
 
I think for anyone to try to offer improvements they would need to know something about the existing system, and how it's wired, plumbed, controlled & operated. Maybe some pictures?

Why two wood boilers? The only multiple wood boiler setup I remember reading about on here is for heating an institution with a monster heat load in frozen Minnesota - they have three.
 
I have a 200 year old house and being in the logging business wood was not an issue. I will post pictures tonight also. The one boiler was helping but not keeping up, I was going threw wood faster than I could keep up. So I thought if there was two I would have more surface area to heat and and turned out to work pretty well. I use the same amount of wood to heat the water and it stays hot. Over 30deg I drop back to one boiler so it burns clean.
 
Its odd to do it with wood standard in the oil and gas heating world. Commercial buildings use line ups of wall hung gas boilers or line ups of oil boilers. They have a master controller that stage the units as needed and rotate them to keep the hours reasonably close. It would be lot easier and more efficient with a large storage tank when burning wood since unlike oil and gas a wood boiler takes hours to turn on and off.

I think most folks would buy a Garn and be done with it.
 
Its odd to do it with wood standard in the oil and gas heating world. Commercial buildings use line ups of wall hung gas boilers or line ups of oil boilers. They have a master controller that stage the units as needed and rotate them to keep the hours reasonably close. It would be lot easier and more efficient with a large storage tank when burning wood since unlike oil and gas a wood boiler takes hours to turn on and off.

I think most folks would buy a Garn and be done with it.

Or one efficient wood boiler + storage.
 
Here is a picture of the front of the old 1979 Tasso boilers. I will get a picture of the busy back side tonight. This picture is from last season when I first tried this two boiler plan, and it was a total fail.
 

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I still plan to replace all the plumbing to larger diameter pipe, after going threw all the trials I decided it was best to keep it simple till I get what works.
One of my questions is would it been better if I had run a loop and just tee'd of the loop to feed each boiler? I think the way it is its dead heading when the W/B circulators are not running and the water is not returning to the OB.
 

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As far as the OB goes, I have the WB supply going into the bottom return of OB and going out the end of the supply manifold in a loop back to the return of the WB, the OB returns tee into that loop too and go out to the wb. I do leave the return valve half open to the OB since I realized the return water cant get back if the wb circulators are off. I have four circulators on the Oil boiler with flow checks on the supply side. If anyone has any suggestions other than scrap it and buy a bigger one, let me know, I would like some advice.
 
I think for anyone to try to offer improvements they would need to know something about the existing system, and how it's wired, plumbed, controlled & operated. Maybe some pictures?

Why two wood boilers? The only multiple wood boiler setup I remember reading about on here is for heating an institution with a monster heat load in frozen Minnesota - they have three.
I went with two because I had them, and one was not enough in the cold months. And a big new efficient one is way beyond my budget. But I have tell you this system has been working almost perfect for my house. I'm very surprised that no one is doing this, I have saved thousands in the last two years. Its rough but it works, I would like to do it again some time with two modern boilers. Or buy a smaller house!
 
I remember seeing a picture somewhere of three Econoburn units plumbed up in parallel.......
 
I know they double up with oil boilers, I'm just surprised that i can't find more people doing what I did. Other than the 4 to 5 hr burn times its doing a great job.