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Wood furnace (boiler) conversion to RMH?

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My family recently purchased a business in Maine. The building is about 3000 sq ft and is heated with a Sequoia Paradise wood furnace. I am able to fit a 55g drum inside the furnace and we were thinking of  fabricating a feed/air tube at the opening of the door. Will a rocket mass heater produce enough heat for our system which circulates 210 gallons of water? When the furnace is filled and running efficiently it brings the water temp to 180. Can a rocket mass heater be designed in a closed area? Here are the specs for our furnace:

Paradise model E3400 outdoor wood furnace. It
has a 320,000 Btu/hr rating, with a forced
downdraft gasification design. The firebox is 44"
deep x 48" tall x 32" wide, holding 39 cubic feet
of fuel. The unit stands 60" wide x 72" long x
94" tall
[Thumbnail for IMG_20181008_152544.jpg]
Posts: 3867
Location: latitude 47 N.W. montana zone 6A
cat pig rocket stoves
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Hi Steve;  Welcome to Permies !

That is one big wood eater you got yourself!
 I would love to tell you a RMH could do that job ... But I can't.

There is a limit to how many btu's are available from a rmh even from a large batch box build.  I think your needs are above that .

I could be wrong and possibly one of the master builders may have made such a beast. If so, hopefully another will post and let us know.  
Posts: 427
Location: North central Ontario
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If its a gasification boiler efficiency wise you are head and shoulders above what standard wood boilers can achieve already. I think controlling your usage will result in better results then modification. It will work far better with dry wood which should be obvious but many people used to the old outdoor furnaces that " can burn anything" will try to burn anything in an efficient unit and have horrible results. Matching your call for heat to the intensity of the fire will go a long way to increasing efficiency as well. Also those gasification boilers are most efficient at full load so if there is any way you can incorporate in home storage that would be a good thing to do. The simmer, heat up, simmer heat up common in forced air linked systems is what kills your efficiency numbers...
Top of head... Cheers,  David
Posts: 3280
Location: Southern alps, on the French side of the french /italian border 5000ft elevation
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Well, how high from the ground is your door?
How wide and tall is it?
I think i would try a huge batch, with the heat riser entering that door.  

You might have to do a broken riser.  May be you Can fit a  12 or 14 inch batch.  

How strong is your draft?

The other thing, you most certainly  will have to make a plunger tube, to use the boiler as a bell.

I think it's time to gather  firebricks,  tubes, and superwool.

I forgot. You might well have to build another bell, since you internal surface area will be too small. And a good idea, would be to build it around the boiler, to heat inside and out. Tho, you will loose heat to the outside surface of the bell.
Yeah, but how did the squirrel get in there? Was it because of the tiny ad?
Rocket Mass Heater Plans - now free for a while
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