Baffles, baffles, baffles!

weissman--

Thanks for the strong suggestion.

Everyone say baffles, and I'm not sure why, but that's what I just bought. I will say though that I wouldn't buy the argument that they're quieter (if that's what someone claims) because on my parent's broan - around 400 CFM, a step up from builder grade - there's no discernable difference in sound at any speed between when the mesh filters are in or out.

Foodonastump - the advantage of baffles is not that they are quieter than mesh. It's that mesh will get grease in it as the exhaust is being used. Now everyone knows what mesh looks and feels like, so this grease in the mesh is easy to picture--and this can happen quickly if you are cooking, say, hamburgers. As soon as the mesh has grease in it, ithe hood become less efficient because the air flow up the hood is becoming blocked. As the mesh gets more of a coating, the hood becomes progressively less efficient. So it's a shame if someone pays a good deal of money for a hood, but it doesn't take much for the hood effectiveness to be compromised. Of course, if you clean the mesh frequently this is not an issue. People have to be honest with themselves about how often they will be cleaning the mesh filters.

Meanwhile, with baffle filters, the same grease of course coats the channels of the baffle filters, but the air flow is not compromised. Unfortunately, hoods with baffle filters tend to cost more. Hoods that are stylish in glass that some people want tend not to be offered with baffle filters. Same with stylish flat hoods. Though I like the canopy-style hoods better myself. Has the more professional restaurant-style look - just MHO.

Baffle filters do not trap all of the grease and some of it escapes behind the baffles and gets trapped on the fan and the blades. Cleaning is not as simple as tossing the baffles in the dishwasher, as the area underneath gets yucky, too.

Does mesh trap all of the grease so I wouldn't have a lot of extra cleaning behind it elsewhere on the hood? If I were religious about cleaning the mesh (throwing them in the dishwasher) so air flow wouldn't be inhibited, would this be as good as baffles? I'd assume with both styles that the "frame" around the mesh or baffles would have to be wiped down, but I really don't want to have to spend a lot of time cleaning the guts of the hood. I am one who prefers lower maintenance type items. Thanks.

On my hood with baffles, I get a little bit of grease in the frame but as far as I can tell, nothing in the guts of the hood. If it's there, I can't see it and on my hood there's no way to get in there and clean it anyway. I've had the hood for over 10 years and it's still working fine. It's an older model DCS hood.

weissman, I couldn't see see the grease on my hood, but when I touched the fan covers after removing the baffles, I could feel it. The baffles catch a lot of grease, but some is definitely escaping behind them, and since air flows in and around the baffles, I don't see how grease behind them can be avoided completely. Since I can feel some sticky grease on the fan covers, I can only assume that it also gets up into the fan and the blades, though I have not attempted to remove the covers and find out. For now I've just been using some degreaser on the exposed surfaces whenever I wash the baffles, but I can't help but wonder what kind of mess is collecting up there where I don't have access. There is a video on youtube that shows how to remove baffles as well as the fans for cleaning, but really, had I known beforehand that grease was going to get up inside there, I might have chosen mesh filters. Like needinfo1, I prefer low maintenance. If mesh filters are better at trapping grease, I'd rather go that route and just throw them in the dishwaser more often.

Mesh won't catch everything either, though at intuitively it would seem it would catch more. A few years ago my mom got some blobs of gunk on her stove and was trying to figure out where it was coming from. Turns out it was grease dripping back from the ductwork. I removed the hood and cleaned out what I could reach. Probably don't want to know what's building up in everyone's ductwork!

I'll offer a different perspective, although my experience might not be applicable to needinfo's situation. I have a shallow depth cabinet mount hood but it sounds like needinfo wants either a freestanding island type hood or a wall mount type.

I also have a small kitchen in an old house with rather substantial achtitectural limitations on where I can put things. (For example, my kitchen layout has to deal with four doorways.) I needed a short-height hood to fit under cabinets above my range. In 2002, I bought and installed a Zephyr Cyclone -- 36" wide, 24 inches deep, 5" high, twin fans, and 600 cfm capacity. (IIRC, the current Cyclones are similar except that the capacity is now 650 cfm, they have halogen lighting, and there is a faring at the back wall -- most of the unit is still 5" tall but it fares down to about 7" at the back wall. Apparently, this is supposed to help with capture.) Anyway, the Zephyr Cyclones do not use either baffles or mesh.

The fans duct air to a grease separator and the grease drains down into removeable, rectangular clear plastic receptacles that hang at the back of the hood. A lot of grease collects in them and every couple of weeks I spray some Formula 409 or Pinesol into the fans while running. This helps clean off the fans and the grease separator. When I clean out the receptacles very couple of weeks, there will be between 1/8" and 1/4" of grease.

So, last year, I redid the cabinetry on the wall above the stove, and took the opportunity to re-route the vent ducting to make it a straighter shot. You'd think there would have been a lot of grease in the ducting after ten years of use. (The vent gets used every day, I do a lot of sauteing and fry-pan stir fry, a lot of steamy things, and etc.). The backflow-preventer baffle/flapper above the hood did require some work with degreasing as did the flapper at the wall vent. But, in between, there was only a very thin film on the ducting. It cleaned up quickly with a spray of WD40 (a fine solvent, btw) and a paper towel. From past remodeling experience, I was expecting much worse.

My Cyclone model is designated as a cabinet-hung model but the supplied instructions advised that I could also mount it as a wall-hung. I don't know if that is true with the current versions of the Cyclones.

Vent-a-Hood has its "magic lung" blower system which supposedly works pretty well although I've read varying opinions here on how easy they are to clean and how noisy or quiet they are. When I did last year's cabinet remodel, I briefly looked into the possibility of getting one the shorter-height VAH models. IIRC, they were about 6" high but were cabinet hung only, and rated at 250 cfm capacity, which was too little venting for what I wanted.

We've looked at Vent a Hood and rejected them for a number of reasons. JW, you're right in that we are looking for more of a wall chimney type hood (we too have more limitations and constraints than you can imagine). We've looked at Zephyrs but haven't seen any with the venting type system you describe, but I imagine that is because we are looking at the wall mounted rather than under cabinet. Thanks for the input.

Is anything wrong with Vent a Hoods? Thats what my KD wants to use and since its a log home we need to vent under the floor.

Is anything wrong with Vent a Hoods? Thats what my KD wants to use and since its a log home we need to vent under the floor.

We just couldn't convince ourselves that Vent a Hoods are worth the premium price one pays for them. If we'd been truly convinced that they are a superior product that produce much better ventilation than competitors and that they were quiet in doing so, we'd probably have still included them in the equation. But, we couldn't.

I think what really eliminated them for us was the quotes that we got for these where a chimney extension kit to extend the reach up to our 9 foot ceiling was somewhere in the $500 to $600 range just for a piece of metal. Many manufacturers sell entire vent hood for less than this. We just couldn't believe that this piece of metal was worth that kind of money in order to buy their product.

You may also want to do some more research on these forums. There are VAH fans here and those who do not believe the claims that their ventilation system is actually superior. And, some people have complained about noise and difficulty cleaning.

JW, my backflow-preventer/flapper is located on the end of the vent run on the piece that is attached to the roof, rather than in the pipe directly above the hood. Do you see that as being a problem? I am picturing my vent pipe getting coating with grease!

Wow, what a timely thread. Today I happen to be researching the cost of mesh filters as am considering a Windster hood with mesh vs. a hood with baffles. The Windster distributor happened to point out the high cost of replacing their mesh filters if one cooks a lot. They are $50 each for mesh and a 30" model takes two. Wow, I'm wondering how frequently those babies need to be replaced for a high usage hood. Could anyone offer how often they replace their mesh filters?

jellytoast:

Not to worry about grease build-up if you only have one flapper.

As I understand it, stuff accumulates on the flappers because they are perpendicular to and hang into the air flow. That means they will act as grease catchers. The ducting is mostly parallel to the airflow and usually will not accumulate much grease: (a) as long as your hood is producing air-flow to move the exhaust air at sufficient speed (which is basically fast enough to keep the flappers open) and (b) as long your hood's mesh, vent, &/or grease removal is not clogged or obstructed; and (c) you are not overloading the system by producing commercial levels of cooking effluent gases (as would be the case if you were cooking dozens of hamburgers for hours every day on a 48" stove or cooktop).

Also, are you sure there is no flapper at the hood as well as at the top? Most hoods I have seen and purchased have come with a flapper & frame to install at the hood outlet and that frame is what is needed to connect the hood to the ducting. My Cyclone came with a both 3x10 rectangular frame/flapper (for venting out the back or top into 3x10 rectangular ducting) and a 6" diameter round vent/flapper (for venting out the top into 6" diameter round ducting. You (or your installer) separately purchase the ducting and the wall/roof-vent flapper.

Of course, it is possible to remove the hood-end flapper and/or install the duct connections without one, and, in theory, that should give you a bit better air-flow up to your roof. In my region (northern Rockies) that would not be worth it. I want two flappers to avoid inviting cold air blow-back during windy days and avoid having cold air spilling out of the chilled vent column when the fans are not running.

This post was edited by JWVideo on Fri, Jun 21, 13 at 15:55

Texasgal- I just called my mom, she says she replaces the mesh filters about every other year, not because they don't come clean anymore but because the mesh starts to separate from the frame.

Like JWV I'd expect to see a damper on the hood, but I just uncrated my Kobe and there is none, nor do the installation instructions call for one. It's just got a 6" round outlet that ties straight to the ductwork.

Foodonastump, thanks for calling your mom. Replacing every other year isn't too bad. That helps quite a bit with my range hood decision. Does your mom still cook quite a bit? I'm wondering if she cleans her filters by hand, or in the dishwasher, that they last so long. By the way, love your "countrified" user name.

She cooks every single day. I will say she doesn't deep fry, wok, etc. but for her normal everyday cooking the hood is on. She just soaks the filters in hot dishwater periodically, I believe. So overall I certainly wouldn't say she puts her hood to the test, but it is used very regularly.

Foodonastump,thank you for the prompt response.

There is no single filter type that collects aerosol grease particles of all sizes within the particle spectrum generated by cooking (possibly excluding intense UV conversion of grease to gases.) One can tour on-line advertisements for commercial filters and see what part of the particle spectrum they are designed for and how well they work over part of the spectrum.

What you hope for in a residential hood is that you collect the larger particles in the filter and the smaller particles exit the ducting before they can condense on the ducting. The result will always be imperfect relative to the goal. Deposition depends on what sizes pass the filter (baffles or mesh, usually) and the velocity of the air in the ducting, and the temperature of the ducting.

Note that Magic Lung centrifugal grease slinging is not that different from how baffles work to collect grease. Like baffles, the Magic Lung squirrel cage fan can only impinge the larger particles against the assembly wall. The fine ones stay as an aerosol in the air flow and are passed up the duct.

kas

Thanks, JW, that's a relief!

Like foodonastump, my hood did not come with a flapper. We didn't realize this until we installed it along with venting out the roof, then felt cold outside air coming in through the hood. I called the manufacturer and they said, "Oh, you need to add a damper, either at the roof or above the hood." Gee, thanks for telling me now after I've got it all installed!! Grrrr. Foodonastump, my installation manual didn't mention adding one, either. Rather than removing the range hood and taking all the venting apart, it was easier to change the roof vent, so we went that route. Don't make the same mistake that we made!

Hm, odd. I've had my Zephyr for 5 maybe 6 yrs and have run the screens through the dishwasher maybe once a year. Even though they never look that dirty. Maybe a slight yellow, barely visible tint. Just do it because i think i should. I run it all the time, mostly on low since it is so darn loud running stronger. I cook from scratch all the time and often 3-4 burners going but never with much 'fry'. Usually just a tiny bit of olive oil. Sounds like your cooking style is not likely to cause concern for your choice.

Help.
I have just had a 36" Island hood installed and my contractor has placed the chimney covers upside down. In other words, the louver vents (two) which should be at the ceiling end of the chimney are at the hood end. Will this make any difference to the efficiency/safety of the appliance? It is 950cfm with baffle filters.
I was not present for the installation and only noticed it after the fact.

Louvres on the chimney? Do you have a recirculating hood? If so, that's definitely upside down and a functional problem.

Otherwise, let me suggest that you start a separate thread on this. Your question may get missed because it is buried so far down in this thread. Also, it is bit off the topic of the title. Really, you may get quicker and better help if you start a separate thread. It is a good idea include the brand and model in the title of your new thread, too.

This post was edited by JWVideo on Fri, Jul 26, 13 at 17:54