It is my understanding that the purpose of range exhaust hoods is to remove heat and moisture from the home.
In TRECs (Texas Real Estate Commision) SOP’s we are required to call out the absence of a range hood or a range hood that does not exhaust outside of the home unless it is a recirculation type.
Can someone please explain to me what good a recirculation type of range exhaust is when all it does is blow heat and moisture right back into the home?
Thanks
Same reason people put black shingles on a house. It looks good. A ventless range hood usually has a thin charcole element filter that “semi” removes smoke. Other than that it does not do much but like you say circulate the hot, moist air back around the room. Most of them blow the offending air right back into your face if you are standing in front of the stove. My report forms has all this pre-printed on it and I explain the ventless hood to the client. Little else you can do.
It is supposed to be for energy efficiency. Say I live in the desert/mountains and in the summer/winter I pay through the nose to condition the air in the living space. Why would I want to suck all of that conditioned air (MONEY) out of my house.
Besides when the wife cooks Sunday brisket it is nice to still know that a week later.
And if you don’t clean the filter you can not only smell brisket but ham from easter 3 years ago…mmmmm ham 
Look at this URL, you might find interesting to this topic.
http://www.ces.ncsu.edu/depts/fcs/pub/8(1)/parrott.html
Hope this helps.
Marcel 
Have you ever realy looked at a range hood? i mean from a functionality stand point. go in you kitchen and look at yours. ask you self, “what 2 burners do i use the most?” then look real good and ask “what are the only 2 burner actualy covered by the hood?” 99 out of 110 will answer “front 2” for the first question and “back 2” for the second question. so do you realy think it makes THAT much difference if it’s vented out or recerculating? a pretty inificiant system if you ask me. but on the other hand, if it did cover all the burners, you’d smack you head on it EVERY time, unless you mount it up over your head.
If one has dry skin, recirculating the moist air helps one maintain one’s youthful looking skin.
If the home is cold, blowing the heat back into the house helps warm it up.
Darn margaritas.
My next kitchen will have a cook top with the exhaust fan that slides up when in use and slides down when not in use. I have now had my last head-denting-kitchen. And you wonder why Ms Margarita, Dr Cuervo, and Dr Micodin are residents in my kitchen.
R Ray, I installed on last year that was in a house of many dollars, and installed in an island cook center. Press a button, and it would come out of the island countertop. It was connected to a 10 inch duct with an exterior wall fan. CFM’s 380 cfm. Your eggs would probably slide from one side of the pan to the other.
Couldn’t hit your head on this one, but might suck the Margarita out of your glass. ha. ha.
Marcel
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Hmmmmmm. Overhead, bang my head, soothe my head with margaritas
or
Underhead, no bang my head, but no margaritas either.
That’s a tough one.
Will require more research.
Fortunately, I have a good research team consisting of me, Ms Margarita, Dr Cuervo, and Dr Vicodin.
That’s funny R Ray. If you are going to have a few while your research team is doing the work, have one on me, what the hell your paying anyway. ha. ha.
Marcel
Hmmmmmmmmmm.
Everyone wants to be on my research team
or
they simply want me to pay for their sins.
Hmmmmmmmmmm.
personaly i like the hoods that are about 6.5 feet off the floor over an island with a 6 burner gas range with built in griddle…hay i can dream too.:mrgreen:
This is one of several I have built for my clients over the years. The blower is mounted outside on the wall and connected with 10" Dia. duct. Great for indoor grilling. When set to high speed it can pick up small family pets.:mrgreen:
I installed an allure by nutone no sharp corners.
Did not go for the cheapest I went for the quietest.
It has six slots under the front and this causes a vornado effect .
It does a great job on low speed removing all the steam from the front burners.
I guess you get what you pay for.
Roy sr
Nice Roy; I still have a cheapy modle that does not suck any air out, just circulates the dirty air in my opinion.
Exhaust fan that works properly, I guess that opens another window about air-exchange and where it comes from. Every CFM exhausted has to be replaced.
Question! Is there enough leakage through windows, doors, gaps, fireplace, attic, wall components, floors, and what not to compensate for exhaust hoods that could exhaust as much as 500-1500 CFM’s?
Is it possible to oversize the kitchen exhaust hoods for the purpose intended?
Are we trying to accommadate our clean-air in home and causing another problem?
Maybe I ask to many question. ha. ha.
Marcel 
Marcel,
You raise some valid points. The blower units that I use are designed for residential kitchens. These are high end blowers $1500-2000 range all stainless steel. The hood, ducting and filters were designed by myself. I take the make up air into consideration when we install these however, in the large homes that I install these it is usually not a problem. I was just joking about the small pets.:mrgreen:
I usually only have to run it on low speed 18 year old home Good windows . I do not see any problems of course it could pull air back through the dryer or the central vacume . I also guess I still have enough comming in through the walss and windows . I also put in quiet vents on timers in both bath rooms Insulated pipes and the best 4 inch vents with springs on steel doors well worth the $14:00 each .
Roy sr 100 CFM comes to mind
Hi. Roy Cooke;
I hope you are enjoy your Neuton Exhaust fan. I have revued some of them and they are pretty fancy. You must be doing alright depending on the model.
I agree with you on the 100 CFM, because it is typical to see bathroom exhaust between 80-110 CFM depending on size of course.
P.S. Too many Roys, the other Roy’s R. exhaust fan is sucking out small critters, I hope it is just in the size of a mouse or overgrown house fly. ha. ha. ha.
Have a good day.
Marcel
nice work Roy. glad to see there are still quality craftsmen around.
