A couple years ago we purchased a GE Monogram 36 "pro Gas cooktop - ZGU36N6HSS at a liquidation. It's taken us more than 2 years to actually start the renovation, but now that it's begun, the decisions/questions are coming fast & furious. We MUST decide on a rangehood & ventilation issues this week so cabinetmaker & HVAC contractor can finish plans & begin ductwork. We are in Florida where I am concerned about making any additional holes in roof & having extraneous things mounted on house b/c of hurricane issues. SO, first question is: Is an in-line blower a reasonable alternative to remote external blower?

The specs on the cooktop require only a minimum of 600 CFM, but the rangetop has 6 burners with 15000btu capability. Seems to me I want a lot more cfm but also concerned about noise. The salesman at the highend appliance store we visited this weekend recommended Best in-line blower F-ILB11 to go with either 42" chimney hood or 36 or 42" (but at least 24" deep) undercabinet hood. Only problem is
this combo was coming out to significantly more $$ than we paid for the rangetop (albeit on clearance).

Any less expensive options?

Thanks, in advance, for any advice!

hard to know what to suggest regarding less expensive options since you don't indicate your price on the Best system. Can you be more specific? If not, I'd at least suggest checking on at least one more option before making decision. I always am an advocate for Modern Aire hoods, but there are others who are big believers in Independent, Prestige, Metallo Arts, and others. In general I'm much more impressed with hoods from companies dedicated to making them, not huge appliance companies that do everything.

I have read your praise of Modernaire & I will give them a call tomorrow. The price on the Best system was $1900 for the chimney style hood and another $690 for the blower. Does that sound reasonable? It seems a lot for a not very fancy setup.

I've seen the Broan blowers for a lot less. Are all the brands interchangeable with one another?

Should have mentioned- we will be venting out to a side wall (although the rangetop in not on an external wall) It's at least 20-25 ft between the rangetop and that exterior wall.

Thanks again for any advice- I find the whole venting thing confounding.

However saying BTU ratings have nothing to do with vent needs is silly. Think about it logically: what are we trying to actually remove with a vent hood? Three things, really: 1) grease, fumes, odors, smoke 2) heat (especially in the summer, to avoid making the kitchen feel like an oven) and 3) gaseous products of combustion (i.e. carbon dioxide, carbon monoxide, and other products of burning gas--obviously not applicable with induction).

So, where does BTU rating impact this? Obviously, with number two, it is the sole determinant. If you're cooking on four 22K burners simultaneously you're putting out a huge heat load, versus someone simmering away on a single 5K burner. So, BTU's are the only factor here.

BTU's also play a critical role in #1. Anyone who's cooked on a high BTU burner, say when we're trying to sear a piece of meat, knows that there is an enormous increase in smoke, grease spatter, odor, etc, when you are successfully searing over 20K BTU's, versus the typical pitiful "it's really steaming, not searing" you get over a builder's grade 8K burner.

So, BTU's do matter. For confirmation, look at any ventilation reference and you'll see that observation. An easy place to see that is on the Wolf website. Look at their vent hoods and you'll see that their recommendations for blower size depend on the BTU rating of the range that is used.

Oversimplification is rarely helpful when making these decisions.

Based on my experience cooking hard over high heat--searing meat, roasting nuts (like the spicy nut recipe from Hayday), stir frying correctly, creates a ton of smoke. The notion that all odor is contained in the grease, and that a filter will capture it all, is in total contradiction to what I see when I cook. Smoke and invisible odors that travel up to my bedroom closet are clearly not just grease-borne.

If your blower is inadequately sized, no matter how large your capture area is, the smoke and other fumes will eventually spill outside of the capture area. More BTU's = more potential smoke/fumes.

Crank up our two ovens and run three or four burners on our range, and I'll promise that running the blower at 1200 cfm clearly reduces the heat load on the HVAC.

Anyway, no big deal, we just agree to disagree.

Many more decisions will be dropped in your lap as this begins to move forward.

We have just completed (well almost) our kitchen renovation after about a 2 year contemplation and 3 + month construction phase.

One item I was adamant about was an effective range hood. We suffered for years with the integrated vent on an Advantium. This thing is useless as a hood - see earlier posts by me in archives.?? Great appliance however and we would never be without it - 220 model. We just moved the thing to another area above our countertop and bought a real hood.

Don't fret too much over the cost. You'll regret it later if you cheapen out. As my dear old dad always says - "It's only money, doesn't hurt you here or there, only in the back pocket for a while". The time you are spending coming up with ideas and making selections plus the labor cost or your time if DIYing it, is more than the added cost of getting the better appliance - IMHO. Plus once you finally get through this you will not want to do anything again to make changes.

We did decide to go with a Best by broan Model UP27E (inline or external fan) since our range is only a 30" - we kept existing range since wife is happy with it and fairly new GE Electric Profile. 30" range has only 4 burners plus a bridge but not the btu of your 36" . We have the 600 cfm inline fan using 10" duct. It works marvelous and do not see the need for more as of yet. Summer may change that but I doubt it. We vent through a sidewall in attic space so no pentration in roof which I would advise against roof units. SLight vibrating noise from unit however and I will try using rubber isolation mounts on inline motor unit in attic which should help minimize that. Motor itself does hum somewhat also and I believe that is a function of the type of motor/speed control. Best should offer an option to upgrade fan motor to a better style of variable speed type control.

HOod design is something I looked at before making decision since I belief these flat bottom screen types are not near as efficient as the baffle / capturing designs. IF using a less efficient hood design up the blower cfm. Also the greater the cfm the larger the ducting will need to be. These are low pressure blowers which need a large surface area in duct size to move enough air. And yes you should consult mfgr specifications for proper cfm to btu of range. Remember you can always turn the speed down but you can not make it flow more than it can handle.

Regarding cost - remember that the biggest part may be installation not the price of the unit! So if a contractor is giving you a price for the unit and installation then of course it will be much higher than what you can purchase it for yourself. these remote blower units are much more work than an integrated hood. Electric must be run to 2 locations as well mechanical work on 2 locations. MAke sure HVAC guy does install properly - not too long a duct run and minimze turns. Also ask him to use rubber isolation mounts for you under blower :)

I'll try posting elswhere on this forum some of our other experiences during KR.

"Thermal plumes of kitchen appliances: part 1 idle mode" and "Thermal plumes of kitchen appliances: part 2 cooking" by Kosonen Risto, Loskela Hannu, and Saarinen Pekka.

There is also a wealth of information other places, such as the extensive set of kitchen ventilation articles somewhere at Greenheck.com

kas

Along w/being displaced out of our home due to construction, for the last 3 days we didn't have phone or internet access in our temporary apartment. I felt like I needed carrier pigeons :)

I'm meeting an appliance person today who, at least over the phone, seems to be trying to tell me that an in-line blower won't significantly reduce the noise over internal blower & it will cut down on efficiency. That seems counter to everything I've learned on Gardenweb.

Again, thanks for your thoughts!

At any rate, a good while back I got frustrated with these kinds of statements and posted a little "experiment" I did regarding hood noise. If you haven't seen it, it's worth a look. And I'll say it again: our Modern Aire hood with fantech FKD 10XL remote blower and LD10 silencer is virtually silent at 1200 cfm while our VAH will drive you crazy from noise at 600 cfm. See the thread for proof!

FWIW, I was concerned about the twisty-ness and length of our stove vent (600 cfm) and couldn't find any info on how to calculate what was necessary. I eventually called FanTech who took all the measurements of length and duct diameter and number of turns, crunched it all up, and said the air wouldn't actually make it out of the building envelope. The guy said the air would just start compacting about five feet from the end...until it couldn't anymore and our fan would stop being effective. So we opted for a booster fan about half-way downstream.

All that said, how come no one talks about distance to the outside? Does everyone just have so short a run that it is immaterial in most cases?

As to distance to outside and hood efficiency. The longer the run and the more turns the higher CFM you must have. Of course it makes a difference. Also you MUST start your hood running at least 5 minutes before you start cooking and leave it running that long after...the air has to get moving and keep moving.

Pics of our hood ,,,setting is on med ( if you have too high a setting it causes a turbulence in the duct and the odors etc come back in rather than go on out...this is law of physics DH says so we have stopped using high)

Miele deep fat fryer:

steaks on Lodge Logic grill pan:

hood liner/cooking area