Smoke Stack Preheater Questions

[BAP]

I have seen other people on here in the past make preheaters by wrapping the smoke stack with copper. Can anybody who has done it tell me what success they have had. Does it work and how did you do it? What size pipe did you use? Thanks a lot.

[Pibster]

I tried it one year. It did warm up the sap a bit, but I felt it wasn't worth the hassle. The following year I went to a parallel flow copper preheater and a steam hood. That will really heat the sap up.

[jrgagne99]

I've done it with 1/2" copper, about 10 wraps around my 6" stove pipe. Flowing about 15 gph through the coil, I got about a 70F temperature rise. It is important to avoid boiling in the coil. If your flow rate is too low, you can boil in the coil and get vapor lock with can completely stop the flow if you don't have enough head pressure. Also need to worry about freezing in the coil after shut-down. Consider a shutoff and vent valve at the top to empty the coil out at the end of the night. But don't empty it too soon, or else the heat from the stack will cause sugar to burn inside the coil.

I used mine for about two years, but in the end, I decided it wasn't really worth all the trouble. I ended up throwing it away. It was fun to try, but never truly satisfied with the results. If you do try it, do very tight wraps and consider using ceramic insulation, covered in tin foil to improve performance.

[optionguru]

Made one this year. Everything seems to work well and going on many others advice and experience I've wrapped 1/2" about 10 times around the 6" stack. I then put a ball valve to adjust flow. I also wrapped the whole thing with 8" stove pipe to make a nice neat package to hold more heat in. I set mine up so when I run out of sap I'll run water through it until the end of the boil so nothing burns in the pipe. Look at my album to see a few pics.

[Aaron S]

Pete. How did you connect your pipe to the pot ? Thanks Aaron Spencer

[optionguru]

Found a 6 gallon pot made for Clam bakes, it had a spout on the bottom for dispensing broth. I attached a plastic hose with hose clamps from the spout to the copper. The plastic remains outside of the jacket that surrounds the copper coil and stack so it doesn't get hot. I think, like others have mentioned, the flow control will be the most important part.

[Aaron S]

Thanks
I have a stock pot that I would like to put a tap on. Looking to see if their is some kind of inexpensive fitting I can get.
Aaron Spencer

[OldManMaple]

Here's a couple of fittings and there are more out there. Search weldless fittings
http://www.austinhomebrew.com/product_info.php?cPath=178_40_131_574&products_id=10057
http://morebeer.com/category/stainless-weldless-kits.html