BSD
02-28-2017, 10:30 AM
I'm looking for constructive criticism to improve my boil rate.
I run an older set of pans, not sure who makes it, but it's 5 pans. overall dimensions are 2.5x10' for the pans. My back three pans are drop flues, the rear most is 8" deep flues, the next pan is 6" deep flues and the middle pan is 4" deep. The front two pans are finishing flat bottom pans. My arch runs a 10" stack with about 17' of height. my first boil I averaged 40 GPH with no blower. I'm certainly happy with it, but with everything, i'm looking to improve and run at peak performance. I get a raging boil in my second flat bottom pan, presumable because that's where most of the heat is over the fire. The middle pan would get a jumping boil at the front to middle of the flues. my 4th pan would simmer very hard but rarely boil unless i forced wood way back into the firebox. My last pan would basically only simmer lightly or act as a pre-heater. Smoke coming out of the stack would really shoot up into the air at start up, it draws extremely hard. I use the ash door to control air intake through the grates for AUF.
My setup: 15791
With the warm spell i cleaned out my pans and in the process i added more height to reduce the gap between the brick at the back from about 3" to 3/4-1" to the flues on the last pan. I also added a vertical row of firebrick behind the flues on my 4th pan. I did this to force some air up into the baffles of the last pan. then after the last pan, before going up the stack i added a 5" piece of metal from the top down. my thought was to trap as much heat and then force it down before going up the stack. the area of my stack is 78in square. and i have 112 inch square of area under the 5" baffle at the rear. I think this also helps slow the heat down a little before going up the stack.
15792
15793
i did a test boil with water and it seems to work well. i got a huge jumping boil in my middle pan, my forth pan was boiling at the front and simmering well at the back, and my last pan was also simmering harder than it ever has before as well. I was able to raise water from 50 to 211 degrees in about 9 minutes in my front pan, which is a bit faster (no real timing though) than i've done it before. my second pan was boiling hard after just 5 minutes.
So i have some thoughts about how to improve it further. one is to put more baffles in with firebrick under the forth and middle pan to create a tumbling wave action and force more heat up into the flues.
My other thought was to raise the bottom row of firebrick even more under those flues. because of the stepped-down size, i'm curious if it would work. The bottom of my arch would have a "hump" in the middle and then get lower before going up the stack due to the nature of my stacked height flues.
My last thought was to make a set of zig-zags channels with fire brick to slow the air flow under the middle and fourth pan, this would also create a little more turbulence, which i think is helpful.
Should i be aiming for a hard rolling boil in the front pan? or do i want it to boil/simmer hard? I think i could get a rolling boil up against the front if i put a blower under the arch where there is a cut out for it. i think the blower would force the heat/flames to the front of the arch before going to the stack.
Any thoughts?
I run an older set of pans, not sure who makes it, but it's 5 pans. overall dimensions are 2.5x10' for the pans. My back three pans are drop flues, the rear most is 8" deep flues, the next pan is 6" deep flues and the middle pan is 4" deep. The front two pans are finishing flat bottom pans. My arch runs a 10" stack with about 17' of height. my first boil I averaged 40 GPH with no blower. I'm certainly happy with it, but with everything, i'm looking to improve and run at peak performance. I get a raging boil in my second flat bottom pan, presumable because that's where most of the heat is over the fire. The middle pan would get a jumping boil at the front to middle of the flues. my 4th pan would simmer very hard but rarely boil unless i forced wood way back into the firebox. My last pan would basically only simmer lightly or act as a pre-heater. Smoke coming out of the stack would really shoot up into the air at start up, it draws extremely hard. I use the ash door to control air intake through the grates for AUF.
My setup: 15791
With the warm spell i cleaned out my pans and in the process i added more height to reduce the gap between the brick at the back from about 3" to 3/4-1" to the flues on the last pan. I also added a vertical row of firebrick behind the flues on my 4th pan. I did this to force some air up into the baffles of the last pan. then after the last pan, before going up the stack i added a 5" piece of metal from the top down. my thought was to trap as much heat and then force it down before going up the stack. the area of my stack is 78in square. and i have 112 inch square of area under the 5" baffle at the rear. I think this also helps slow the heat down a little before going up the stack.
15792
15793
i did a test boil with water and it seems to work well. i got a huge jumping boil in my middle pan, my forth pan was boiling at the front and simmering well at the back, and my last pan was also simmering harder than it ever has before as well. I was able to raise water from 50 to 211 degrees in about 9 minutes in my front pan, which is a bit faster (no real timing though) than i've done it before. my second pan was boiling hard after just 5 minutes.
So i have some thoughts about how to improve it further. one is to put more baffles in with firebrick under the forth and middle pan to create a tumbling wave action and force more heat up into the flues.
My other thought was to raise the bottom row of firebrick even more under those flues. because of the stepped-down size, i'm curious if it would work. The bottom of my arch would have a "hump" in the middle and then get lower before going up the stack due to the nature of my stacked height flues.
My last thought was to make a set of zig-zags channels with fire brick to slow the air flow under the middle and fourth pan, this would also create a little more turbulence, which i think is helpful.
Should i be aiming for a hard rolling boil in the front pan? or do i want it to boil/simmer hard? I think i could get a rolling boil up against the front if i put a blower under the arch where there is a cut out for it. i think the blower would force the heat/flames to the front of the arch before going to the stack.
Any thoughts?