I am adding a vent through an exterior wall for my over-the-range microwave which currently recirculates.Two wall cap options:Imperial VT0515: this one has a well sealed and weighted damper but the outlet is even smaller than the inlet, leading me to think it will restrict flow. The inlet is 3-1/4” x 10” while the outlet is about 2” x 10”.Broan 639: this one has a large outlet but a low quality damper that will need extra foam weatherstripping at a minimum.Thoughts? The microwave fan is rated at 250 CFM and either of these would be mounted directly against it with no intermediate ducting. via /r/DIY https://ift.tt/2ShU8DA
