We have the Wolf 36" sealed burner rangetop with 6 burners and Wolf also recommends 900 cfm.

We purchased the 42" Wolf Pro Island hood and external rooftop mounted 1500 cfm blower. The 1200 cfm would probably have been adequate, but the cost difference was minimal and the 1500 has much more pressure capability. Remember, you need a lot more airflow for an island installation, especially one with a charbroiler.

The hood is absolutely gorgeous. Ha, too bad it will be months before everything is installed as this is all DIY.

If the VAH is 600 cfm, then it's 600 cfm, it's not going to flow 900 cfm. The only thing "magic" here is the hand-waving VAH is doing. I looked at the VAH products before purchasing the Wolf and frankly I was underwelmed. They didn't seem that quiet in the store and the underside didn't really look that great since it was just painted metal, not gorgeous stainless baffles like the Wolf.

Yes, the Wolf does cost more, but in the end I think you get what you pay for. Since this island hood will be a very prominent feature of our kitchen, which is totally open to the dining and family rooms, we wanted something that looked great and also did the job with minimal noise. Hopefully, we'll have that combination... I know we have the looks part :-)

Good luck with your decision.

Tom

I have the 36" df Wolf w/charbroiler and the 600cfm 36" VAH. The range is mounted against a wall. This arrangement is about 90% effective, meaning 9 out of 10 cooking situations it is working well.

In your island setup you may want more cfm's because of the air disturbance on all sides of the range.

Make-up air may be an issue depending on how well your house is sealed. It may also be a code issue as well. When I turn my VAH on high I need to open the windowscreen abit.

Enjoy the charbroiler. You are sure to have a lot of fun with it and the new menu ideas that go along with it.

I have a 36" Bluestar with grill and a 1200 CFM VAH hood. Wall mount.

In my opinion, 600 CFM will not be anywhere near enough with the grill. 1200 CFM is fine, on a wall, but islands generally need more CFM.

If you mount the hood real low, you might be able to get away with 600 CFM, but I would go for 1200 CFM. Remember, you can always turn off or lower the fan power, but if start grilling up something smokey, and you don't have enough CFM, you will wish you had more!

"If the VAH is 600 cfm, then it's 600 cfm, it's not going to flow 900 cfm. The only thing "magic" here is the hand-waving VAH is doing. I looked at the VAH products before purchasing the Wolf and frankly I was underwelmed."

We have not yet selected a hood but I am not sure I agree with your statement there. What you are interested in, is the amount of air being moved. This is a function of the power of the blower and static pressure in the line. The baffles increase the static pressure, which reduces the effective airflow. So all else being equal, the unit with lower static pressure wins. By the same token, I can easily see the possibility that the same 600 CFM blower, would move more air than identical blower having to get over the resistance of the baffles (and much higher mesh filters).

So what I am hearing is that a 42" 600cfm Ventahood is not going to be adequate, even if it has a supposed "900cfm" effective rating?

I really hate to jump to a 1200cfm in a harsh climate like Minnesota and have to go with a bigger make-up air system.

Any other thoughts?

-Owen

Ummm.....move somewhere warmer. Or cooler and less humid in the summer. (Ex-Minnesotan here) Really, can't think of a great answer for you, but you really should go with the 1200cfm EXTERNAL blower. The Wolf 600cfm internal was incredibly loud, and not nearly enough "oomph" to prevent our smoke detectors from going off every time we used our charbroiler. Having said that, the charbroiler IS a lot of fun to use and works very well!

Re: blower power and cfm... blowers are usually rated at zero static pressure. Thus, when you install a unit "rated" at 900 or 1200 or whatever cfm that is only under ideal conditions with no back pressure. Once it's installed with exhaust ducting, termination fitting, etc. the actual flow will be less.

When Wolf or any other manufacturer says they recommend 900 cfm they probably mean 900 cfm at zero static pressure because they do not know how the blower will be installed.

I don't believe VAH ever actually says their 600 cfm blower will flow 900 cfm, just that it's supposed to flow "the equivalent" flow of a typical 900 cfm "regular" blower. I'd like to see a fan curve for their blower and see what the cfm versus static pressure looks like... because I still do not buy their claim... and they provide NO information on their website to back it up.

Aside from this, the other thing I did not like about VAH was each blower only operates at two speeds, Low and High... and if you set one to High and one to Low they fight against each other and make more noise. The Wolf, and others, have infinite speed control so you only use the power you need.

I can post pictures of our Wolf hood and external blower if anyone is interested. The motor and fan on the external blower makes the small in-the-hood blowers look like the Tinker Toys they are :-) This setup is not for everyone of course due to installation requirements and cost, but in the grand scheme of things of our major ($$$) remodel we felt the extra cost was justified. YMMV.

Tom

We have a Tinker Toy set-up actually up and running and working quite well for us. Go figure.

I've read your posts trashing VAH and apparently you have issues with them. I think you have the full subscription.

Let us know when you have a system that is installed and actually operates.

ocmetz187 - your concern about moving the heat out your MN house with a high cfm blower is valid. We have noticed the temp in our house drop by a couple of degrees while the hood is in use on a high setting. That said, when things are cooking at a temp high enough to use those settings, the food is cooking fast and the fan won't be needed for too long a period running at full tilt. The Best hood has a variety of settings that are quiet and responsive. The grease and odors generated by your Charbroil element need an effective escape route, especially in an island install. If you have some working showrooms in your area, go visit and see how various hoods work. See if your Wolf distributor has a Living Kitchen so you can see your rangetop in action and the ventilation they use. Planning is time consuming, but for the time and expense a new kitchen entails you want to make sure you have components that optimize your cooking experience.

Variable speed is indeed nice and we like that feature on Viking that we saw (and the easy to replace baffles). And agree that there is little speed control on VAH. Having said this, I was surprised how quiet VAH was on a fully vented display model, obviating the need for slower speeds. Our Gaggenau hood in the current house, is far prettier but also noisier. It uses mesh filters so it is bound to be noisier but still, there is a distinct difference and I prefer VAH to Gagg even though the latter has multiple speeds.

As to external blowers, I have been told that if they break down, it is very hard to get them serviced since technicians may not want to climb the roof and/or be insured for it. I don't know this first hand though but thought I mention it ;).

BTW, we still haven't decided which way to go for our second remodel so am not defending VAH because it is in our house....

If heat exhaustion is a concern, then get a HVAC specialist involved and have a heat recovery unit installed on the vent, as well as engineer the makeup air system to avoid bringing in cold air. It's more costly, but the energy savings may be worth it to you in the long run.

Or, you may decide that a pro grade range and all of the headaches that go with it just isn't worth it for the type of cooking you actually do and go with a nice consumer grade range and hood that will eliminate the need for high powered venting at all.

Hey john.com, when you get a fan curve from VAH, please let me know :-) As for trashing VAH, I don't think that pointing out things I personally don't like is trashing them. So, let me point out one other thing... if you want more than 600 cfm you need to have, what, four blowers... which requires a double transition, which requires a high ceiling height, which won't work for everyone, including us.

Anyay, I'm just stating my opinion like everyone else on this list. If you love VAH, great :-) Go figure.

Don't need the "fan curve"

Your words from above..
>> "The motor and fan on the external blower makes the small in-the-hood blowers look like the Tinker Toys they are"

Sure sounds like trashing to me. Maybe I need to re-read it.

>> "If you love VAH, great"

Thank you. I can't believe you said somthing positive about VAH.

Owen,
Anytime you are dealing with a charbroiler on a piece of cooking equipment you are going to need an absolute minimum of 900 CFM. You also need to take into consideration the overall length of duct run and the number of elbows used in the run. If you have a lengthy run of duct and a number of elbows you may need 1200 CFM. Your local dealer will be able to help determine your needs based on the total BTU's of your range and the variables I have already mentioned above.

I also want to try to clear up some of the other things that have been mentioned in this thread. VAH's statement regarding equivalent CFM is something that is often unintentionally misrepresented due a sales staffs lack of understanding or more likely a sales reps lack of properly explaining it during training. The truth of the matter is that, many (not all) manufacturers rate the CFM of their "blowers" not the entire system including filters. VAH tests the entire hood system. The equivalent CFM statement is based on these differences. When you introduce filters there is approximately a 33% drop in stated CFM, thus a VAH 600 CFM system performs equally as well as a competing 900 CFM system from another manufacturer. Since VAH's system is a patented centrifugal extraction style system, no filters are required so when the hoods are tested the result is true CFM ratings. Many people think an external blower system is quieter than an internal system. External blowers are actually no quieter due to the fact that you are still sucking air across a filter which is where most noise in a ventilation system is created. VAH does offer a remote system that is typically used when there is a restriction in the width of the hood. It should be noted that a VAH external system is no better or worse than another external system and the VAH external system offers none of the features of the patented magic lung system.

"Aside from this, the other thing I did not like about VAH was each blower only operates at two speeds, Low and High... and if you set one to High and one to Low they fight against each other and make more noise. The Wolf, and others, have infinite speed control so you only use the power you need."

I have to disagree with the statement above. The truth is, each blower in a VAH system is in its own housing. So if it is a dual blower there is no possible way for blowers to "fight against each other" as air does not mix until after is in the duct work. In addition to that, based on sound testing done by the same third party tester HVI uses, it has been proven that adding another blower in a VAH system adds little to no additional noise to the system whether 600 or 1200 CFM which is something that is not possible with an infinite speed control. As far as fan speed is concerned, a VAH dual blower 600 CFM system offers speed selection of 300,450, & 600 CFM. The fact that there is not a variable speed switch is intentional for the reasons I mentioned above. 300 CFM has been proven to be the minimum CFM required to extract grease no matter what type of filtration system. Anything less is simply not effective in removing grease from the air stream. It should also be noted that at no time are the motors in a VAH system exposed to the flow of greasy air. The same cannot be said for a filter style system. At the end of the day, tinker toy or not, a 75 yr. track record of no fire claims is testament enough to the fact that VAH just works.

Owen
Basically your best bet would be to use a 42" wide hood as you stated, be sure the hood covers the front burners and the front of your charbroiler. Mount the hood 30-32" above the cooktop and have a minimum of 1000 cfm. If VAH is 600 cfm, stay away, go to 900 if your must, but not 600. VAH does say their 600 is the same as a filtered 900, but I assume they are talking about mesh filters, where there is quite a restriction. Todays baffle filters do not restrict much air at all, that is why most restaurants use them. Again, pick any hood you like, but 1000 cfm, should be your guide.