My range hood is 1000 CFM and requires 8" duct. I reduced it to 6". On max it produces a lot more noises. It is always the best if you can follow manufacturer's recommendation. It's there for a reason.
-jeffrey815(Smartiecat);
2018-11-28(#11815910@0)
没的compare，要compare you need to have a set up with 8" vs. 6" side by side. You can google to get a theoretical comparison.
-jeffrey815(Smartiecat);
2018-11-28(#11815970@0)