It is ok to have too much claimed airflow. First, you won't get that much airflow for various reasons described in numerous posts in this forum. Second, given a means of controlling the motor, the fan can always be run at a lower power level if that proves to be sufficient for a given cooking operation, thereby reducing the noise. A ventilation system with a 10-inch duct system and 10-inch blade diameter blower should be pretty quiet moving a real 600 cfm, and even quieter at the 400 cfm that the 600 cfm rated system would have likely actually moved, depending on MUA resistance.

Turbulence noise will at least drop with power reduction, and while I haven't looked this up, my guess is that it is proportional to the square of the blade tip velocity, so running at half motor power may reduce noise power by a factor of four. So aim for a hood that provides continuous control of the blower motor, and find a good operating point for each type of cooking, saving maximum noise for the rare (unless you are running an Asian restaurant) extreme effluent dishes.

kas

Thanks, kas, I was hoping you'd respond. I appreciate your expertise, even if it always takes me several read-throughs to understand the techno-lingo.

Do you have any suggestions to add to my list? Or do you know where I can find a list of baffle filter hoods? I've tried various searches but the results haven't been helpful as yet.

Thank you!

I was told recently at an appliance store that the continually-variable/rheostat fans make a buzzing sound at lower speeds. There weren't any hooked up at that store so I couldn't test it out, but, if the claim is accurate, that might be something to check in advance to see if it impacts your ear issues.

lisa_a - try searching at ventingdirect.com. You can search on just about anything for range hoods including baffle types.

I can only augment the comment above by suggesting searching on this forum (using Google, perhaps) for hood related topics, making a list of hood names that are raised in the topics, and then finding the manufacturer's web sites.

You may also come across store names that you might contact.

kas

Thanks, AvatarWalt, I wouldn't have thought to check that feature and how it might affect me.

Good idea, kmg67! Thanks!

GW's search function is nearly worthless so I always search via Google, kaseki. I'm still sorting through the list of threads I turned up in my last search. So much info, not enough room in my brain to absorb it all. :)

By the way, I hear no buzzing with my continuous blower control on my Wolf hood, although if this is a sound induced in the blower motor, then with my blower mounted on the the roof I wouldn't be able to. The local control circuit in the hood is the decades old triac/diac design that GE published around 1970, or perhaps earlier.

With a local in-hood blower, buzzing might result if the motor windings or laminations have enough play.

kas

Thanks, Kas, I'll be sure to ask my appliance saleswoman about this when I meet with her next week.

Wish I could do a remote blower but that would mean taking the venting up the wall and through a bedroom window. Not likely to go over well. :)

Wolf hoods are one of my contenders. They have a good rep and they're made in America.

After much research, we're likely going with a 42" Best range hood (but it's not to late to change out if someone has concerns!). They have a 600 cfm internal blower, which has some fancy iQ technology.

Here's some specs on one of their midpriced models:
http://www.bestrangehoods.com/Libraries/Reference_Sheets/UP26_iQ_Reference_Sheet.sflb.ashx

It's halogen, not LED, though.

Thanks, RChicago!

I've narrowed my choices to either a VAH or a Modern-Aire hood. They offer 600 cfm and smaller hoods that I can vent directly out the back wall. It's too costly and way too complicated to vent the hood vertically (there's a large bedroom window in the way).

I had to rule out a number of others because they either were ridiculously overpowered for my needs - no way could I avoid MUA costs - only vented vertically or required at least 24" of vent pipe to vent to the rear (couldn't accommodate), or were too expensive.

I've read through dozens of old threads about ventilation, plus I've consulted several experts (ventilation reps and CMKBDs) and I've concluded that 400 cfm will fulfill my needs. I know that's going against GW wisdom that bigger is always better but oh, well. :)

Our 20 yr old pop-up downdraft is rated at 500 cfm for our standard gas cook top (rarely used it on high, too danged noisy and it sucked the flames sideways). And yet I'm quite sure that a 400 cfm hood will easily beat the ventilation pants off that old pop-up downdraft.

I'm leaning towards the Modern Aire. I like its appearance plus, at 24" deep, it has a better capture area than the 300 cfm VAH (only 21" deep).

In case anyone else is on this same quest, here's the list of possibilities I compiled, in no particular order:
Imperial
Prestige
DCS
Wolf
Modern Aire
Viking
VAH
Kobe
ZLine

A few brands never made the list because they were poor qual1ty. I looked briefly at Best but their baffles were backed with mesh (what they apparently call their hi-low filter system), which is not what I wanted.

This post was edited by lisa_a on Fri, Sep 26, 14 at 11:31

Stacked filters aren't always bad, but they are not usually necessary.

(a) For residential use, one would want to be sure that the second filter was not too close to the first and thereby interfere with the flow direction reversals that baffles depend upon to sling the larger end of the grease particle spectrum out of the airflow. One would also want to be sure that the selected blower had the capability to meet its airflow requirements at the now likely doubled (or worse) pressure drop across both filters.

(b) For specialist commercial use, where more of the grease spectrum has to be removed before ejecting the air to the outside, there are systems where two or more filter schemes are stacked for greater coverage of the particle size spectrum. Besides baffles and meshes, I've seen ball-bearing loaded cannisters promoted. For ultimate grease particle elimination, intense UV is used.

kas

After looking at the VAH today, we scratched it off the list. Cleaning it is much easier than I expected. They changed the design so it's a simple matter of pulling out the grease tray. However, DH did not like how visible its inner workings - the squirrel cages - were. He thought it looked unfinished.

So we're deciding between Wolf and Modern Aire. And we're going to go with 600 cfm after all.

Don't think I could go wrong with either of the above. The hard part will be deciding which one to choose.

This post was edited by lisa_a on Fri, Sep 26, 14 at 18:52

I stumbled across this post and curious how did you resolved your kitchen / vent issue?

We are looking at replacing our 1990’s gas cooktop and downdraft with a 36” gas range top and 42” vent hood. I was looking at the VAH and MA brands of hoods. (Yes I know it’s an ugly kitchen, but the rest of the house makes up for it) I will need a good hood because I will probably go with a pro-style 36” range top. I am still deciding on Thermador (have now), Wolf, GE Monogram, etc.

My installer said he could remove the existing cabinet uppers to install the ducts and vent directly to the outside. The old down draft ducts are the wrong size anyway so that brick needs to be patched up.

I am not ready for the BIG $100K remodel, but this would be a baby step forward and I would have 4 working burners and my kitchen to not smell like bacon on Sunday. Thanks!