Quiet range hood (remote blower options?)
I thought for sure this would have been discussed here already, but I cannot seem to find actual product recommendations, regarding quiet range hoods.
I understand there are many factors to consider before discussing brands. I.e. I don’t need crazy CFM, so going with a lower (400 or so) CFM blower is one way to keep noise down. I also plan for larger ducts without lots of bends. I have also read that having a hood much larger than the stove really helps with capture, to the point that it can make up a bit for the lower CFM.
Design-wise, I am looking for either an insert or a chimney style wall mount hood. Z-Line hoods pop up as an obvious choice, and they look decent, but they unfortunately don’t publish noise ratings. I have read a few reviews that menti0n they are a bit loud in terms of airflow noise (the grill design?) even when using a remote blower.
Are there other options I should consider that have similarly priced offerings but are known to be quieter?
I am consider remote blower for the reduced blower noise and because installing it in my situation does not seem much more difficult than an integrated blower.
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I’m a fan of the remote blowers, sometimes called “inline centrifugal fans”. If you have a mechanical space above the kitchen or an unused attic space it will be much quieter for you. You can also do this trick for bathroom exhaust fans as well, and even use one fan for multiple bathrooms if it’s strong enough. Or use smart-switch controlled dampers to ensure the room calling for exhaust is wide open while the other room is the closed or partially closed.
So you're a fan of fans - well played ;-)
maine_tyler,
Fantech sells a variety of remote fans and hood silencers.
https://www.fantech.net/support/frequently-asked-questions/kitchen-ventilation/
My own hood is too noisy. I have trouble telling whether it is from the motor or mainly just the air movement.
I have two Zline's in my kitchen and don't find the noise excessive. They're very good at capturing cooking gases.
I'm curious: which models are you running, and are you using the remote blower or local blower options?
I'm liking the offering of Fantech's motors. Their hood inserts... not so much.
I kind of wish I could pair a ZLine (or similar) insert with a fantech blower. Does anyone know of other inserts that can be sold without the blower?
I also stumbled upon Vent-a-hood, which seems to take a different approach (no baffles?).
Maine - what do you not like about the Fantech insert ?
Well, perhaps I should be fine with it (if you are familiar with it I'd be happy to hear experiences).
3 things:
1)To my untrained eye, the duct terminating as an abrupt 90 into the shallow liner looks terrible for airflow. I would expect reduced suction at the periphery and a general increase in noise. The Z line is tapered, which just seems like it'd function better, but it may not be of significance.
2) Halogen lights (minor, but I would like LEDs)
3) The baffle area looks a bit smaller on the Fantech than on the 46" ZLine. That said, its really hard to tell from a picture how good the baffle set up is. My impression is that the baffle design actually matters quite a bit as far as sound and grease trapping capabilities. Whether the Fantech baffles are actually worse, I don't know. Perhaps they're better...
My theory is that the larger the baffle area for a given CFM, the less airflow noise, so I would look to maximize baffle area for a given dimension.
I did find this video discussing the install of the Fantech set-up:
https://www.youtube.com/watch?v=h7eXuwkfDm0
There was one commentor on there that took serious issue with the silencer being a grease trap / fire hazard...
Maine_Tyler - the reason I asked was because I had just purchased one (I should have noted that). The only thing I can say at this point is that it was straightforward to configure & order and received it in a few days. I was under the impression that Fan-Tech was a leading ventilation manufacturer and just went with it without researching it too much.
But thank you for the feedback - things I don't think I would have even considered, especially the silencer as a grease trap concern by the one guy and the potential baffle design / airflow issue.
My only option is to vent through the roof. I went with the roof mount fan. I plan on putting the silencer after the bend from the hood closer to the fan and will be able to access it in the small conditioned attic space, which falls in line with Fan-techs recommendation.
I really dislike fan noise so I'm excited to see how this works out. Now I have to figure out how to make it automatically turn on/off (I'm the only one in the household that uses the fan !)
I am certainly no ductwork/airflow expert, so my concerns about the shape of the liner may be completely unfounded. That fantech makes it, and also that the guy in the linked video (Corbett Lundsford who is a bit of an HVAC fanatic) used it probably means it's not such a bad design. And the more I looked at photos, the more I think the baffle area is comparable to the Zline or maybe even slightly better. At this point I may be leaning towards going with the fantech setup, but it's times like this that I wish it were possible to see the different systems fully installed (in the same configuration) to see how they actually perform/sound in the real world.
If it's a Fantech EC fan, see my posts. It's not hard to automate them at all given the new 0-10V wireless control modules released in the last year or two.
Denniswood - thanks for the info, I'll definitely take a look at this !
Wolf has liners and remote blowers
I was intrigued by Fantech's remote blower for range hoods when I was looking into replacing my 1980s recirculating range hood last year. I didn't find a ton of references to it aside from a Home Performance video on youtube (same guy in video linked to above, different video). I wanted something quiet enough that I would use it, easy enough to clean, real buttons vs a touch screen, less than 400cfm so I wouldn't have to deal with makeup air, and a finished range hood that wouldn't need me to build or pay for a custom range hood cover. Since I was also switching to an induction range I didn't feel the need for massive CFM like a high powered gas range may require. It was frustrating that most companies seem to equate quality with having a touch screen vs buttons. My wife hates touch screens and I have no particular love for them.
https://www.youtube.com/watch?v=bMkvCn1sGvk&list=PLyMS7H6dB-4bZdRqTOttqI3PDGEcnBiiZ&index=4
I realized the fantech remote motor, hood, and potentially one of their silencers as well would add up to over $1,000 and I'd still need a custom range hood cover. I still considered it, but was happy when I found a much cheaper and simpler option to suit my needs.
There are likely better options out there, but the 30 inch cosmo stainless steel range hood has been well worth the $220 I paid for it, with LED lighting, baffle filters, and real buttons, one for low, medium, and high speed, along with one for the lights and other to turn off the fan. I did 6 inch rigid ductwork sealed with foilmastic butyl duct tape. I would have gone wider than 30 inches but the 30 inch model perfectly fit my cabinets and as it is I usually get great performance on low and rarely need to even go to medium speed. Of course having an induction range means I'm mostly removing cooking fumes and moisture vs much of anything actually burning. The fan isn't silent, but I've only been in one person's house with a quieter range hood and they were very proud of it. I've been in more homes with gas ranges and no exhaust at all.
https://www.amazon.com/gp/product/B00SB4R4J2/
Exhaust hoods with built in fans are generally pretty bad when it comes to real world scavenging efficiency. My approach was to purchase an inexpensive hood, remove the built in fan and use an inline ECM fan which is far more effective, and a lot quieter. I've gone a few steps further to automate on/off and speed settings based on how much power the induction cook top is using. Although there is a manual on/off switch, no one uses it as the ECM fan fires up and sets speed based on the induction cook top operation. After 2 years in testing/operation, I'd highly recommend this approach. More here including specs, performance testing for flow, sound etc:
https://www.garagejournal.com/forum/threads/automate-kitchen-exhaust-hood-fan-using-inline-ecm-fan-turbocharge-yer-exhaust.491330/
With the automation bits, I'm also able to run the HRV in make up air mode which is unbalanced during kitchen exhaust fan operation by about 100CFM. In a tight house, it definitely makes a difference when measuring inside vs outside pressure with a differential magnehelic gauge.
Appreciate these thoughts.
Putting aside the hood itself, I'm starting to rabbit hole on what the optimal blower would be. I notice most ready-made products use squirrel cage blowers.
Fantech offers a couple options, namely a 'centrifugal inline duct fan' and a 'mixed flow' fan which "combines the high airflow of axial fans with the high static pressure characteristics of backward curved impellers."
There are EC versions of the inline duct fan, but not the mixed flow (in the right duct size).
They also have exterior wall mount fans, but I'm not sure how I feel about hanging the fan in the elements. Also not clear what type of fan/blower these are exactly.
Does anyone know what type of blower would intrinsically be the most quiet and perform well? I am tempted by the EC fans because I have heard they operate quietly at low load, whereas some NON-EC motors hum do to the speed controls when not on full.
On the other hand, industry standard for hoods seems to squirrel cage blowers. Google searching appears to talk up squirrel cage blowers as quiet and good at overcoming static pressure, but they're usually comparing against axial fans. I don't think the Fantech options are really 'axial' since they use centrifugal action.
Fan gurus?
The Terrabloom fan I used for the exhaust (EC fan, mixed flow) actually has a pretty decent curve with respect to resistance. See attached. I used that model specifically for the kitchen exhaust because it has a metal case and meets code here. It's rated at 288 CFM at zero static. Doing it again, I'd place the fan up in the attic instead of 2 feet or so above the hood. This way I could use a longer inline duct silencer and make the system almost silent. Regardless, it's still much quieter than the OEM hood fan and flows at least 75% more air in my restrictive duct setup. The Broan Ecovent (exterior high efficiency vent hood) uses an EPS foam ball/insulated socket and at -30 C will frost slightly..the OEM fan could not "pop" the ball, but the Terrabloom fan at full speed has no issues with this. The automation system runs it at 100% for about 30 seconds at start up for this reason.
I took some actual CFM measure measurements of the system in use. I did not test speeds 1-4 as they are too low for effective venting.
Speed Setting 5 - 111 CFM (this is what I have it set at for pretty much 100% evacuation)
Speed Setting 6 - 124 CFM
Speed Setting 7 - 131 CFM
Speed Setting 8 - 162 CFM
Keep in mind that the exhaust vent is about 10 feet long in total, reduces from 6" to 5" t0 4" and exits in a 4" Broan Ecovent. CFM numbers like those ( with relatively high static pressure) are excellent. Speed setting 7 and 8 are pretty much overkill capturing steam/odours from cooking. 5 and 6 work great. Using the fan at speed 5, where we have it set, requires 18-19 watts of power.
Sound readings about 1 meter/3 feet from the hood:
Speed Setting 5 - 57 db
Speed Setting 6 - 61 db
Speed Setting 7 - 63 db
Speed Setting 8 - 65 db
We don't actually use these exact "speed" settings now as the EC fan controller (Zooz Zen54) allows you to choose from 99 different steps. The simple automation code calculates the exhaust fan speed based on power use at the induction cook top. Before this, I just used the included speed controller manually set to 5, using the existing hood's fan switch to toggle power to the fan. More here if you want to play with automation: https://community.hubitat.com/t/success-0-10-volt-control-of-ac-infinity-or-any-ec-fan-motor-using-leviton-zs057-d0z-zigbee-dimmer-or-zooz-zen54-zwave-0-10v-dimmer/104450/44?page=2
I've also been using the 4" and 6" fans from AC Infinity (EC, mixed flow, inline fans) and they work quite well in my HRV setup. The 6" EC fan is rated at 352 CFM, 65 watts, at zero static. I'm seeing a measured 110 CFM (max speed) from the 6" fan but the HRV system has an external carbon filter (8"), HRV core, MERV13 filtration (14x14x4), inline PTC heaters, inline duct silencers, and about 13 feet of duct on the supply side.
I spoke briefly with a Fantech support person. When I said I only needed/wanted 400 CFM they thought the FG series would be a good fit (vs the FKD). When I asked about hum noise when running non EC motors at part load, he said yeah, they are split capacitor motors and when speed controlling them you get a harmonic hum or something. So the EC version will be quieter in that regard.
I've used a Broan under cabinet hood that I must say was actually quite quiet on low and medium. I don't recall a humming and I also don't think the motors were EC. I am wondering if either the hum is just very faint, or if Fantech is using different motors than what you'd find in an under-the-cabinet Broan type of unit.
Either way I guess feel a bit better about an EC fan if going through the trouble of installing a remote blower.
Which reminds me, if installing a nice set-up like this with an EC fan, it seems like this could be used for a general exhaust ventilation strategy in lieu of a bath fan, no? In other words, run the kitchen exhaust on low on occasion (timer?) even when not cooking. Obviously exhaust only isn't the most highly recommended ventilation strategy in general (especially for tight homes) but for older houses that aren't tight and lack ERV's and aren't going to put one in any time soon...
maine_tyler,
Why not? I suspect the main reason the range hood is usually not chosen is noise.
The EC fans I've been using have been pretty much dead silent at slow speeds. I've tested Terrabloom 6", AC Infinity 4" and AC Infinity 6" fans.
Using one of these for a bathroom fan (I'd use an AC infinity inline EC fan as they have a plastic case) would be pretty smart, although you'd want to install a switch like the Leviton ZS057-D0Z which can both toggle the fan on and off, but also control EC fan speeds via the 0-10 volt wires. That Leviton switch is zigbee enabled so can run in "dumb" mode or integrate with an automation hub. Best of both worlds there as things can get pretty smart with the addition of an automation hub. I like switches like these as they offer a visual cue as to what is going on with automation, and offer manual control as well. See the attached pic which illustrates how to connect the switches 0-10 v low voltage control to an AC INfinity fan.
https://www.leviton.com/en/products/zs057-d0z
I'd bet that EC fans, and 0-10V (already a standard in commercial HVAC) control for both fans and dampers will factor heavily with residential HVAC sooner than later as they are not only very efficient, but can integrate easily with automation so for example a bath fan at 50% speed and a kitchen exhaust running at 70% speed could in turn trigger make up air at exactly the right volume. In my setup the kitchen exhaust fan speed is dialled in (and adjusted live) according to the wattage used by the induction cook top. Make up air is dialled in via the HRV which can run in asymetric flow during fan operation. More importantly for efficiency, these fans and ventilation rates are all dialled back or turned off when not needed, minimising power use and BTU loss.
So Tyler, a simple exhaust strategy that varies EC fan speed with CO2 levels for example in your home, bath etc. is quite easy to sort. It's also quite easy to implement full speed on motion detection(in a bath), timer and/or humidity. The physical switch offers about 10 speed settings and via automation you have from 0-99 to choose from.