Looking for a Low-CFM Range Hood
I’ve spent dozens of hours looking for a:
Modern looking 36″ wide stand alone hood (for over a 30″ induction range)
Less than 300-400 cfm (for a super tight house which will have a Zehnder and some type of makeup air)
An external blower, or quiet for other reasons (such as a silencer but which also doesn’t work with most off the shelf hoods)
A good capture area (i.e. not flat at the bottom, which most one piece units have)
A tall stovepipe without a seam (doesn’t seem to exist)
The only external blowers <400 cfm that I can find are Fantech and the S&P SWF, but I have no idea what hood I can use them with, other than making my own by paring them with an insert and building something around it that has a good capture area.
Other than that I seem to have to give up an external blower or silencer, have a crappy capture area, and live with a stovepipe seam.
So irritating when there are literally thousands of choices and none that work out of the box for tight houses which everyone should be building 🙁
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Take a look at a 36" Victory Twister Island hood. I've used their wall mount version and it is a decent hood for the price.
It does have an a big blower, you can always disconnect it and plumb it to the external blower, but I think the better option is to use the oversize blower but turn down the speed. This tends to be pretty quiet.
P.S. Their wall mount version does come with a 350CFM blower.
Thanks for the lead. That has a lot of good features and I do need the wall mount actually.
You do know that the fans are multi-speed right?
Yes but because my house is so tight I want to move in first before I figure out how elaborate of a makeup air system I want and with a fan over 400cfm I have to put the makeup air system in before I move in. Plus I keep hearing how higher cfm are going to mess up my zehnder.
I believe the Zehnder Q series are all self-balancing so that will help somewhat.
An ECM fan will be variable speed and quiet. It should be possible to set an upper limit on the speed range control, lower than the fan's capability if that's what you want.
Yep and those few times you need full power just open the damn window!
That doesn't pass code though and a makeup air system will be required. (Which will be done eventually, just don't want to do it before I move in.)
I would check exact wording of your local code. Ours doesn't require makeup air system in a house with no combustion appliances.
Most ERVs can handle a fair bit of unbalance, something like the a ComfoAir Q350 can handle 0.8" of pressure.
I am using a modern looking 36" Vent-A-Hood recirc over a 30" induction stove. I also have a Zehnder Q600 and the kitchen exhaust is about 10' from the hood. It does a good job removing smoke and odors.
I like that style but all the studies show having a larger volume than those flat ones helps a lot with capture efficiency. But Vent-A-Hood is good so they probably have a good capture efficiency. It also helps that you have those cabinets next to it. Studies show that helps quite a bit. But I wonder what your particulates and cooking chemicals would actually measure with re-circ. I know a lot of PH people are doing it but based on the new research I doubt it's really as effective as we'd want.
I think a good portion of the nasty things that come from cooking are eliminated just by switching from gas to electric. If I had a gas stove and was frying steaks in a pan every night then I would go with an externally vented hood. For what I am doing, the recirc is fine. I have multiple IAQ monitors in the house and I don't see a noticeable jump in VOC's when cooking. Granted I am not measuring particulates, but at nearly 400 cfm between the recirc and the Zehnder, I am comfortable that most of the bad stuff is being dealt with. There are a couple of things I would do different in hindsight. First, I would have made the counter depth 27" instead of 24". This would have allowed me to use 15" wall cabinets which would have helped even more with capture (and provide a little more counter space too). Had I done that, I would've also lowered the hood height a few inches. The manufacturer recommends a hood height of 24" which just seemed way t0o low for comfortable cooking, but it is better for capture. By moving the countertop front edge out but keeping the cooktop the same distance from the back wall, the cooking angle would have changed enough to allow me to lower the hood a bit.
I also should note that even when not using the hood, the Zehnder does a really good job of removing at a minimum cooking smells when running at anything above vacation mode. The other night we cooked a chicken in the steam oven. We had 3 days of 100% outdoor humidity thanks the Hurricane Henri. First floor RH was 50% and 2nd floor peaked at 59% before turning on the dehumidifier and setting the Zehnder (ERV) to vacation mode, which brought the levels down below 50%. Typically, I never smell the remnants of what we cook, but even the next day I could still smell the chicken on the 2nd floor.
This is a weird way to look at things since electric changes nothing in regards to what comes off the pan and food. This suggestion mostly comes from people with vendettas against using fossil fuels more than anything.
What is the reason for the 350CFM rate? I've personally never wanted a smaller blower on my hood when cooking, if anything, I would prefer one at least 2x what I have now for those times when things are really sizzling.
I would install an oversized blower and not use on max unless a window is cracked.
It's usually to avoid having to put a complicated, expensive, finicky make up air system in due to code requirements.
So to make sure I understand - if the CFM's are under 350 we can skip the makeup air altogether because that's low enough inbalance for the ERV to figure out on its own?
I'm in the market for one right now too and am toying with getting one with three speeds up to 600CFM and figure I could just crack the window whenever I use it the top speed.
we are using thishttps://cyclonerangehoods.com/range-hoods/inserts/bx212/ but also considered this https://www.trailappliances.com/vent-a-hood-34-inch-300-cfm-custom-hood-ventilation-hoodfan-bh134sldscnf
I am adding some info here a little bit late but for future readers...
I am in Ontario Canada. My HVAC engineer added this note to our HVAC drawings: "Any dwelling that contains a spillage susceptible appliance or has a kitchen exhaust that exceeds 350cfm must adhere to 220.127.116.11 and 18.104.22.168 of the [building code]." When I check the code, I don't see specific CFM figures so this might be an engineering calculation.
I mention this because we thought of buy a high CFM fan, like 900 CFM, so I could run it at the low speed and not deal with lots of noise. A 900 CFM system was going to require me to install a return air system and the engineer was insisting that i would need to have a 25KW (yes 25KW) inline duct heater. We decided to install a smaller CFM fan, but invested in making it super quiet.
I bought all my hood vent equipment from HVACQuick online. They offer quite a bit of explanation helpful to homeowners and easy access to manufacturer specs at your finger tips.
They have a 36" Fantech hood vent insert product, which is apparently just an OEM product. The hood insert has an 8" round pipe outlet on the top. I was amazed how the insert pulls air from the entire surface of the unit, not just where the 8" round outlet that is located on the top. I built a super simple modern looking hood vent cover out of wood, basically a rectangular skirt, a flat top, and a U shaped wood cover to hide the vertical HVAC round pipe.
You can pair the hood insert with any size external fan as far as I understood (check with manufacturer), just use a duct reducer to match the size of your fan inlet.
By the way, I installed an external fan in the ceiling and put an HVAC silencer on the inlet and outlet of the fan. I can barely hear the fan running when I use the hood vent - it is absolutely amazing.
By setting up your system to be quiet, you can run it on the max speed of 350 or whatever CFM and not be bothered in the least by the noise. In the end, I have a low CFM system that produces almost no noise and does not required a return air system.
We are all eletric in a home that is below 0.20 ACH 50. No fossil fuel means not chance of co2 backdraft. We can always crack open a window if we feel we need to when running the hood vent.