Venting Large Kitchen Range Hood

ChuckEA

I am installing a 42" exhaust hood that needs to be vented through the back wall. The unit has 2 openings each measuring 3 1/4"H x 10"W aligned horizontally with a 2" separation. Unfortunately the openings do not line up with the framing members of the wall to allow the vents to pass directly through the wall. To solve this, I was going to cover the existing openings and cut new ones that are shifted approximately 6" so that they will line up with the stud bays. Before I proceeded I thought I should check with the experts. What do you guys think? Is there a better approach to this?

locofoco

Usually when you have 2 openings as you're discribing, one is for exhaust one is for make-up air. I assume this is a residential hood over a trophy stove. Are the openings on the back or the top? What do the instuctions say. How do you terminate the ducts outside? Are there instuctions with the hood?
We neen more info.

ChuckEA

The hood is a Dacor model EHD4218. The openings are on the back wall of the unit and I am planning to terminate them with 3 1/4" x 10" wall vent caps. Since the hood is being mounted to an exterior wall, I will be able to make a straight shot through to the outside. I have the mfg's installation instuctions but they don't talk about relocating the exhaust openings. Attached is a rough drawing showing the original and proposed layout of the exhaust openings.

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go dart

1. header off the stud, then make your opening. this isn't easy but neither is reworking the exaust.
2. vent thru the top, elbow to an availiable area. open soffits? now you have a trim oppurtunity

locofoco

I'm not familiar wih that model. Are the fan(s) directly attached to the back of the rear openings? Will the fan(s) move with the openings? Sounds like if you do this you will probably void the warranty. Not something I would want to do on a $1000.+ hood. It's too bad you have to cut two studs- one wouldn't be so bad.

ChuckEA

Thanks for the input guys. The fans are mounted on the bottom and draw air up into an enclosed space (plenum) and can't be moved. The unit is designed so it can be vented through the top through a 10" round opening or through the back through 2- 3 1/4" x 10" rectangular openings. The instructions recommend using the top but I dont think I can vent through the top since the ceiling height is low and the space above is finished. As long as I kept the cross sectional area the same, I was hoping I could just relocate the back openings a bit which would eliminate the need to mess around with the wall framing. Attached is a drawing of the side view.

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