2x6 steam hood fan

[Maple Producer]

Hi yall How big of fan is used in a 2x6 steam hood? How many cfm is suggested? I have a 2x6 leader evaporator and I need to make a hood for it Thanks!

[maple flats]

No fan needed in the hood. In fact, run the stack straight up, thru thew roof. If you ever add a pre-heater in the stack, add a damper that you can lock in position. Then adjust it until you just start to get steam leaking where the hood meets the evaporator, at full boil, and open it very slightly more, then lock it in place.
On my 3x8 evaporator I have 2 hoods, each has a 15" stack. The hood over the syrup pan is elevated about 14" or so, and that stack has no damper. The Flue pan hood sets on the flue pan and it also has a 15" stack. I adjusted the locking damper years ago the way I described, when at full boil and never needed to change it again. Before you add a pre-heater you don't need any damper and certainly no fan.

[Maple Producer]

I should clarify my situation. My evaporator 6 foot away from a window and I was going to run my pipe up and out the window do I still need a fan? To go straight up i would need to go through an attic and roof and I dont want to if I dont have to! thank you!

[maple flats]

That way, I'm not sure if a fan might be called for. Once you get outside, do you plan to go up higher? That might improve the steam movement. I might suggest going up some, then on an incline to get out rather than level. You might just need to test it.

[Maple Producer]

Honestly I am not sure probably straight but willing to do what it takes to make it work! I am not real familiar with hoods so..... Will an 8 inch duct be big enough for a 2x6? You sure are helpful! Thanks!!

[NhShaun]

Straight up would be best but if you don't want to get involved in going through the attic then a fan may help. It will likely need to be made for wet applications and have a pretty high heat tolerance if it's going to last very long in the direct path of the steam.

[Maple Producer]

Ok So is 8 inch pipe big enough? And how close should the fan be to the hood?

[NhShaun]

If you have an adequate inline fan i would guess 8 inch pipe should be enough. Don't forget to deflect the condensation buildup on the steam pipe from entering your sap pans, especially if the pipe is galvanized. Not having the pipe vertical will probably allow water from the steam/condensation to run along the bottom like a little river to where it meets the hood connection and then straight into your pans.

[Maple Producer]

Ok thanks i will try to rig something up for that.