|
|
Post by peterberg on Feb 1, 2015 2:34:29 GMT -8
Hi Max,
You know, all the proportions are important. Some are really critical and others aren't that much, like depth of firebox. What you are doing is looking at one or two aspects and declaring it's close enough. It's impossible to predict what the thing will do in this case. However, the fact that the barbecue is smoking depending on circumstances isn't a good sign, at all.
|
|
|
|
Post by satamax on Feb 1, 2015 4:10:22 GMT -8
Yep Peter, i know. But it was real short in terms of heat riser. Pish easy way, i'll lenghten it. And give it a try! no barrel or anything. I don't want to use the green machine in the new workshop. I'm sure i need bigger. So i'll experiment with this one . See what i can do with barrels and stones. And if not enough, i'll delve into the 220mm tubing. I have between 400 and 500m3 to heat. Drafty, R1 in walls, R3 in the roof.
Thanks again for your help.
|
|
|
|
Post by satamax on Feb 2, 2015 10:40:06 GMT -8
So test has been done, not smoking after the minutes mark, if that. I added 50cm to the original 80, insulated temporarily with rockwool. I will carry on the "research" in the original thread.
|
|
stoker
Junior Member
Posts: 61
|
Post by stoker on Mar 9, 2015 14:16:02 GMT -8
The table in the first post has a mistake: in the 3" system, the batch-box height should be 6.48", but it says 8.5 (eight and eight-sixteenths).
|
|
|
|
Post by pinhead on Mar 10, 2015 12:36:23 GMT -8
The table in the first post has a mistake: in the 3" system, the batch-box height should be 6.48", but it says 8.5 (eight and eight-sixteenths). Fixed. |
|
|
|
Post by pyrophile on May 8, 2015 10:27:45 GMT -8
It seems that the spreadsheet does'nt give primary air's hole dimensions. Peter said 20% of riser"s csa but I also read (from Peter too) 25%.
Would it be possible to add this to the spreadsheet?
Thanks a lot
Benoit
|
|
|
|
Post by shilo on May 9, 2015 10:10:29 GMT -8
25 include the p channel.
|
|
|
|
Post by pyrophile on May 11, 2015 8:50:29 GMT -8
Thank you!
Benoit
|
|
|
|
Post by gdauderman on Jun 15, 2015 15:38:29 GMT -8
I am building an 8" batch box as per Peter's dimensions for our greenhouse. In all of the rocket stove examples I have seen there is an approximate 2" gap at the top of the heat riser and about 1-1/2" on the sides. Does this hold true with batch boxes?
|
|
|
|
Post by peterberg on Jun 16, 2015 0:07:28 GMT -8
No. Batch boxes does need a much larger gap, personally I would say one foot as the top gap. As for the side gap, I would regard 4" as an absolute minimum. Mind you, the top and side gaps can be as large as a yard without hampering the combustion.
The 2" top gap for J-tubes is also a minimum, it won't hurt to have a much larger gap. See a bare combustion which can be run outside and working beautifully, where only the sky is the limit.
|
|
|
|
Post by shilo on Jun 16, 2015 6:35:36 GMT -8
personally I would say one foot as the top gap. As for the side gap, I would regard 4" as an absolute minimum
for which csa riser?
|
|
|
|
Post by gdauderman on Jun 16, 2015 10:26:59 GMT -8
Thank you for your help everyone. If I have a 20' Mass heater on the end of this (i envision if to go out 20' make a return with a 90 & a T so I can clean it out and then return 20', and then 90 up 10' and 90 out of the green house. I would assume I would use 10" HVAC ducting?
Also forgot to clarify if when you said 4" on the side, is that 4" per side - 8" total or 2" per side - 4" total?
|
|
|
|
Post by peterberg on Jun 18, 2015 3:04:30 GMT -8
personally I would say one foot as the top gap. As for the side gap, I would regard 4" as an absolute minimum for which csa riser? That would be for a 6" diameter or 177 cm2 csa. |
|
|
|
Post by peterberg on Jun 18, 2015 3:15:56 GMT -8
Also forgot to clarify if when you said 4" on the side, is that 4" per side - 8" total or 2" per side - 4" total? All around the riser 4", means 8" total. My new heater is growing, it's built in parts by a friend. Have seen it today and it looks enormous. All around the riser there's 9", under the firebox 11", top gap around 3'. Seeing this construction one would think "this probably won't work". The space between working excellent and not at all is presumably quite narrow with this heater. Time will tell which side of the demarcation line it will go. We are still some months away from completion. |
|
|
|
Post by gdauderman on Jun 18, 2015 9:15:48 GMT -8
Thank you Peter! Any thoughts on using red clay for the inside of the flue liner? Superior Clay says they fire is at 2500F when making it. superiorclay.com/fireplace-firebox-design/clay-flue-liners/The 8" is 8" iinside and 9-7/8" outside. I would use the 12" - 14-1/2" outside and use vermiculite and foundry cement for the insulation in between. Or do you think just cutting fire brick would be better? |
|
