Hood exhaust size?

[syrupdreamer]

I am adding a hood to my 2X4 drop flue pan this year. Anyone care to help me with what size exhaust or steam tube to use. Also wonderinf if anyone would care to share their preheater ideas. thanks in advance

[briansickler]

I noticed that Leader went to 8" steam stack on all of the 2' wide models. I'm guessing they had good reasons for doing so. I would go with that.

Brian

[syrupdreamer]

thanks for the info brian

[kiegscustoms]

I ran a 2x4 hood with a 6" stack last year. It seemed to restrict the exhaust too much although leader recommends you have a damper in the stack. We ended up with a lot of condensate in the condensate pan as well as dripping back into the flue pan. Partially because the condensate pan was too big, but still I would run an 8" flue of a 2x4 Hood. I made up a copper parallell flow preheater last year and it worked very well. You need to know how to solder pretty well to fab. one of these. Make 2 2.5" copper boxes out of copper sheet metal about 18" long with end caps, drill 8 1 1/16" holes in the faces and 1 hole in the bottom of each box, cut 8 1" copper tubes to the length you want, solder the boxes together with the end caps, and then the tubes into the holes, get 2 copper unions and solder them to the bottom holes, and drill a 3/8" hole in the top on the high side and attach a piece of 3/8 copper pipe that is higher than your head tank to release the steam. I use the unions so I can remove the entire unit for cleaning. This process goes fairly quickly and easily with the use of a metal brake, drill press, 1Lb soldering iron and a good Mapp torch. I have made 4 of these units and it takes me about 4 hrs to make one. Serpentine preheaters are much easier to make using lengths of pipe and elbows and sweating everything together. I have seen that style get "steam locked" which can be dangerous. The parallel flow style there is always a common air space above the heated sap where the steam can be released. Just my 2 cents