Pre-Heater on stack

[Rick_Seebeck]

I have welded a nipple in the bottom of an 8 quart stainless stock pot and attached the pot to the side of my stack with large band clamps. From the nipple I attached a valve and from the valve I ran 3/8 copper pipe three wraps around the stack and then over the pan.

Thoughts on the design?

[benchmark]

That's how my preheater was ran on my barrel rig. Looking around on the site you'll find that a number of people did the same.
The only trouble I had was trying to take the copper off around the pipe when the fire is still going. I placed a 3/8 flair gas valve on the outlet side of the pipe and regulated the flow with that. I found that I could only have the sap down to a trickle in order to have it coming in a decent temp. The only other problem I had with it is would vapor lock if the flow wasn't fast enough. But all and all it worked well with the small setup i had.