Externally vented microwave – 4in and 6in vent pipe
Hubbadub
| Posted in General Discussion on
Hi,
Just bought a microwave oven that can vent externally. It has the standard 3.25 x 10in vent , and I’ll get a square to round adapter fitting. Just found out that it requires a 6in vent pipe. Problem is that there is an existing 4in vent pipe opening in the roof. That is not going to change.
I’m considering two options: (1) use a 6in to 4in reducer pipe at the microwave and run 4in ducting from the microwave to the roof, or (2) run 6in duct from the microwave up to the roof vent and then use a 6in to 4in reducer at the roof vent.
Question to the forum is: understanding that there will be a 4in duct section at some point, is it better to be restricted at the microwave or further downstream at the roof vent?
Thanks!
Replies
Well, don’t know squat about what the reduction would do but getting it up higher might lower the sound of the restriction. Easy fix, turn to medium instead of running it full bore.
Or
Get the kit that filters the air and blows your hair if your tall. Self venting.
What’s the cfm rating on this micro?
Thanks Calvin, Microwave supports 300cfm
Yea, venting back into the room is really not the goal, has never been satisfactory woth previous units.
300cfm?
Outside of the noise being higher, I don’t think you’ll have a problem. Run 6” till you get to the roof. Hopefully you won’t blow the damper off.....
I would run 6 as far as you can, then if you ever reroof go 6" all the way.