Sugar shack smoke stack question

[valleyman]

So the sugar shack smoke stack consists of duct tubing made up of a 2’ horizontal section, elbow, then up 10’ vertical. Problem- The system is outside of the shack hence exposed to the elements and the horizontal piece rots out every season or two. Any suggestions on how to protect it? I was told to drill a drain hole. Thanks in advance! Ps- I no longer use the pre heat coil feed tank system)
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[SeanD]

It's hard to see it clearly in the picture. Are you saying precip. is coming down the smoke stack and rotting the horizontal piece from the inside? If so, a stack cover will take care of that. A cheaper version is to put a bucket over the top in the off season or when you are not boiling. If you use a metal bucket you can put it on when you are finished boiling.

[darkmachine]

for many years the end of our arch was outside the shack we used old metal roofing to make back wall of the shack next to the stack. Our chimney was made out of 1/4" steel material though, it collected scale but never rusted out. it was outside until last season we build a new arch and moved the whole setup just inside the metal roofing so it's out of the weather. re used the whole stack just cut the width down. Still need to do something about a roof jack though.

[valleyman]

Thanks woodville! Yeah the pic sucks. I do cover the stack after use but the moisture is still finding it’s way down. I’m not sure if it’s rusting more from inside out or outside in. As I’m now thinking since I’m not using the pre heat and rear tank feed any longer, I’m thinking that there area can probably be more enclosed by boxing it in with cement board or maybe corrugated roofing material making sure there’s ample space around the stack.

[wobbletop]

I think the heat rusts out the thin wall duct tubing. Easier/cheaper just to replace it every couple years than trying to make it last longer.

[buckeye gold]

I think the heat rusts out the thin wall duct tubing. Easier/cheaper just to replace it every couple years than trying to make it last longer.

I agree. I use single wall stove pipe and I have to replace it every other year, inside and out. The heat just breaks it down. The only way to avoid it is go stainless or heavy gauge.

[therealtreehugger]

I put a nice new metal roof on my barn-turned-sugar shack this summer. Previously, I had a 90 deg turn out the window, and another 90 deg turn up for the 6" stack. You can imagine how much draft I didn't get. While the new roof was getting put on, I figured now is the time to put a hole in it, so I had a boot put in that would accommodate a double walled 8" (essentially a 10") SS pipe. (yes, changed from 6 to 8"). Double walled SS is a little pricey, so I had thought that once I got a bit above the roof, I could go back to single walled. I need 8' above the base of the boot to meet the required 2' above the peak, which is less than 10' away. The shop where I am getting my stuff said I need to go double walled all the way up, and there is no adapter to go from double to single, without trapping water and possibly freezing and leaking when not in use.

Question is: Should I really go double walled all the way up? The attachment of the double walled to another piece of double walled seems stronger, and less likely to blow over (even though - yes - I have been told I should stabilize the top piece with wire). And its not going to break the bank.
Or : should I reduce to single walled after going up out of the boot about 4'? I could use a collar to shield it, as it goes from double to single, same as the collar that goes around the double walled at the top of the boot?

I am leaning toward double all the way up as I want to do this ONCE, the right way.
Comments?

[ecolbeck]

Is there a way to angle the pipe while its on the inside of the shack and have it exit near the peak? That way you could run single wall on the interior and then transition only at the peak.

[therealtreehugger]

hmmm . . good idea, but the boot in the roof is already over the evaporator. The main idea was to eliminate the bends, and go straight up. A small angle along the roof line probably wouldn't be bad, but I am past that point of no return.

[wvfdc4]

I think the piece you are looking for is called an appliance adapter. It is what would be used to make the connection to a wood stove etc. I have installed a few on wood burning appliances and not had an issue. As far as water I can't imagine an instance where there would be enough water clinging to the wall of the pipe for long enough to cause a problem before the arch rusted out.