A mesh is ok if kept clean. Calculate area that is actually aperture (probably only the mesh area) in square feet and multiply by 90. That is the actual flow rate needed (cfm). Take the fan rating and multiply by 2/3 and that is the likely actual flow rate achieved past the mesh and through the ducting. These are gross estimates, but at least give you something to aim at.

Finding the mesh area for that hood may be difficult without a bottom up view. That hood is also somewhat short, front-to-back. But we might anticipate that the scope of cooking that will be attempted may not require maximum hood performance. (Technically, this means that the likely uprising effluent velocity driven by pan temperature will be lower than maximum and effluent divergence angle may be less than maximum, thereby covering up some hood configuration sins.)

I would go for 24 inches wide in this case.

kas

"here are no decent 24" induction it looks like"

The US selection of 24" (600 mm) induction cooktops models sure is small. Summit (who makes -- or at least brands -- the hoods you are looking at) has a 23" wide 4 burner induction cooktop which is carried by AJ Madison. My recollection from "the Induction Site" (www.theinductionsite.com) is that somebody called Kenyon offers a 2 burner 24" wide induction cooktop.

A quick google search also turned up a Kitchenaid 4 burner 24" unit. Mainly available from Canadian retailers but there does seem to be at least one US retailer who sells it, Seattlehomeappliance.com. The model number is KICU540BSS.

As for a hood, I second kas's advice on getting a hood that is wider than the cooktop, if you can fit it in.

You asked about an OTR unit, but that those may be out of the question for you because all of them are (AFAIK) at least 30" wide.

If that is not unworkable, there are other considerations. They typically have limited pick-up/intake -- the intake vents are usually in the back which does not help much with pots on hobs closer to the front of the counter. You could run a 2 burner hob lengthwise along the counter under the vents where it can manage decent pickup. Alternatively, if memory serves, LG has a 400 cfm OTR model that has a slide out vent that extends a set of intakes over (or closer to) front burners. It got some decent write-ups here a year ago. If you want to search for them, my recollection is that Nunyabiz had one for his gas NXR range and Luv2Putt used one with his viking induction range.

Another suggestion: If you decide to go with one of the 2-burner cooktops from Wolf, Gagg, Miele, Cooktek, etc., you might consider getting a portable countertop induction unit for use at times when you need more than two hobs.

This post was edited by JWVideo on Sat, Feb 1, 14 at 21:39