Post by jermoll on Jun 24, 2015 14:39:21 GMT -8
Hi Gents, and Ladies-
I have built a 16' wide x 24' long greenhouse on my farm which I hope to heat with an 8" j-tube RMH. This project has taken longer than I thought due to some health issues, but I am again moving forward. The greenhouse will include two rows of 9 -55 Gallon half-barrels in a barrelponics system similar to that built by the Zachary Bauer group, shown on www.youtube.com/watch?v=JWq6WJ5TDic. I had some double wall poly carbonate, precast concrete floor, and used storm windows, bought most of the lumber, so my cost on the greenhouse is approximately $2,300.00.
I am using two 275 gallon totes, buried for thermal and UV protection, as fish tanks. Here is a photo-bucket link to show the project --http://i12.photobucket.com/albums/a203/Jerry_Mollenhauer/IMG_1186_zps2hpy3dry.jpg Let me know if you think the added pictures of my neighbor in her two piece are appropriate here. My son got the totes, plastic drums, steel drums for me for free. With the pumps and plumbing, and the grow media (going to haul two #1300 pound supersacks of expanded shale from Kansas City to Minnesota), I will spend about $1,000.00 on the aquaponic systems.
Today, it is 78 deg. F outside, 107 deg F. in the greenhouse. No place to cool your beer. In winter, the rocket mass heater will hopefully bring the temp from the lowest of -20 F to 45-50 F. We will see. Otherwise it is a 9-10 month / year system.
The 8" j-tube RMH I have cast per Matt Walkers pattern and mix design. For the 15' long bench, (two duct lengths, total 28') I am using 16 gallon steel drums, cleaned and split lengthwise as duct runs, with a 30 gallon split steel drum as a 180 degree transition.
My free air calcs are as follows-
8" burn tube- 7.5"x 8" = 60 square inches
14 LF bench duct runs from stove to turnaround - 1/2 16 gallon barrels, so 14"x 14" x.785 divided by 2 = 77 s.i.
180 degree transition -1/2 30 gal barrel, so 18.5" x 18.5" x.785 divided by 2 = 134 s.i. I have just installed a homemade takeoff collar for a clean-out to let me run a vacuum hose down both sides.
14 LF bench duct runs from turnaround to chimney stack- 1/2 16 gallon barrels, so 14"x14" x.785 divided by 2 = 77 s.i.
I believe that the above dimensions for everything downstream of the stove burn tube, are generous enough to draw OK, albeit a bit slowly, which is fine to retain heat in the clay bench. Does this look like a workable plan to more experienced folks here?
My biggest concern is that I cannot get "off the shelf" single wall chimney pipe larger than 8" diameter, so I am hoping that 8"x 8"x.785 or 50 square inches will be large enough to draw well. I plan on running the chimney about 4 feet higher than the roof peak. Can anyone tell me if this is workable, or should I try to fabricate a larger (10"?) diameter chimney? I will install a clean-out at the bottom of the chimney to add heat to start draft.
Also, while the actual burn tunnel is 4" of insulated clay/perlite/furnace cement, the 55 gallon riser chamber will discharge down onto the recycled precast panels I have set in place for the floor. Should I be concerned heat spalling in this area (no open flame here)? I could put down a 2-3" layer of perlite/clay mix at the discharge point if need be. I had hoped these 4" concrete slabs would also contribute to the thermal mass.
Your advice and expertise has gotten me this far. I hope to be raising tomatoes by my 67th birthday in August if my "tail holds out"!
Please let me know if you believe the free air profile dimensions above are suitable for the bench sizes and progressivly large enough to retain a fair amount of heat in the bench plus draw well enough to take the smoke out of the building?
Thanks to all, any comments and help are appreciated .. I have bought Ianto's book and read most every thread here, but I have learned that extra eyes provide extra care. Thanks for your comments, Jerry
I have built a 16' wide x 24' long greenhouse on my farm which I hope to heat with an 8" j-tube RMH. This project has taken longer than I thought due to some health issues, but I am again moving forward. The greenhouse will include two rows of 9 -55 Gallon half-barrels in a barrelponics system similar to that built by the Zachary Bauer group, shown on www.youtube.com/watch?v=JWq6WJ5TDic. I had some double wall poly carbonate, precast concrete floor, and used storm windows, bought most of the lumber, so my cost on the greenhouse is approximately $2,300.00.
I am using two 275 gallon totes, buried for thermal and UV protection, as fish tanks. Here is a photo-bucket link to show the project --http://i12.photobucket.com/albums/a203/Jerry_Mollenhauer/IMG_1186_zps2hpy3dry.jpg Let me know if you think the added pictures of my neighbor in her two piece are appropriate here. My son got the totes, plastic drums, steel drums for me for free. With the pumps and plumbing, and the grow media (going to haul two #1300 pound supersacks of expanded shale from Kansas City to Minnesota), I will spend about $1,000.00 on the aquaponic systems.
Today, it is 78 deg. F outside, 107 deg F. in the greenhouse. No place to cool your beer. In winter, the rocket mass heater will hopefully bring the temp from the lowest of -20 F to 45-50 F. We will see. Otherwise it is a 9-10 month / year system.
The 8" j-tube RMH I have cast per Matt Walkers pattern and mix design. For the 15' long bench, (two duct lengths, total 28') I am using 16 gallon steel drums, cleaned and split lengthwise as duct runs, with a 30 gallon split steel drum as a 180 degree transition.
My free air calcs are as follows-
8" burn tube- 7.5"x 8" = 60 square inches
14 LF bench duct runs from stove to turnaround - 1/2 16 gallon barrels, so 14"x 14" x.785 divided by 2 = 77 s.i.
180 degree transition -1/2 30 gal barrel, so 18.5" x 18.5" x.785 divided by 2 = 134 s.i. I have just installed a homemade takeoff collar for a clean-out to let me run a vacuum hose down both sides.
14 LF bench duct runs from turnaround to chimney stack- 1/2 16 gallon barrels, so 14"x14" x.785 divided by 2 = 77 s.i.
I believe that the above dimensions for everything downstream of the stove burn tube, are generous enough to draw OK, albeit a bit slowly, which is fine to retain heat in the clay bench. Does this look like a workable plan to more experienced folks here?
My biggest concern is that I cannot get "off the shelf" single wall chimney pipe larger than 8" diameter, so I am hoping that 8"x 8"x.785 or 50 square inches will be large enough to draw well. I plan on running the chimney about 4 feet higher than the roof peak. Can anyone tell me if this is workable, or should I try to fabricate a larger (10"?) diameter chimney? I will install a clean-out at the bottom of the chimney to add heat to start draft.
Also, while the actual burn tunnel is 4" of insulated clay/perlite/furnace cement, the 55 gallon riser chamber will discharge down onto the recycled precast panels I have set in place for the floor. Should I be concerned heat spalling in this area (no open flame here)? I could put down a 2-3" layer of perlite/clay mix at the discharge point if need be. I had hoped these 4" concrete slabs would also contribute to the thermal mass.
Your advice and expertise has gotten me this far. I hope to be raising tomatoes by my 67th birthday in August if my "tail holds out"!
Please let me know if you believe the free air profile dimensions above are suitable for the bench sizes and progressivly large enough to retain a fair amount of heat in the bench plus draw well enough to take the smoke out of the building?
Thanks to all, any comments and help are appreciated .. I have bought Ianto's book and read most every thread here, but I have learned that extra eyes provide extra care. Thanks for your comments, Jerry