I'm not a pro and I know very little about MU air, other than we needed to install a system when we redid our kitchen. I know nothing about the Magic Lung Blower. But I'm pretty sure the pros on here will tell you that you need to get a hood with 700 cfm. And yes, you will need the make up air system.

It would be best to start any quest involving kitchen ventilation to study the literature, or at least study the many many threads here on the topic. I would prefer to write answers to questions that are based on my possibly inadequate previous writing than generate yet another long message covering the entire topic. You may wish to start with the "Hood FAQ" which can be found by searching. I believe it is listed under @opaone.

Hoods are about capture and containment, and success in this depends on many factors, the most critical of which is sufficient air flow velocity at the hood entry to ensure that which is captured is contained and expelled from the residence. This velocity is independent of how many burners are running at once, but rather what the cooking surface temperature is plus plume heat augmentation by gas burners.

In any case, the 100 CFM per 1000 BTUh is derived from certain standardized commercial hoods, not residential hoods. See the Greenheck Guide available at https://www.tagengineering.ca/wp-content/uploads/2015/02/KVSApplDesign_catalog.pdf for comparison between the 100 CFM per rule of thumb and the hood aperture velocity rule. I suggest 90 CFM per square foot of hood entry aperture, and this aperture needs to be large enough to overlap the rising and expanding cooking plumes.

Let me adjust the salesman's statement: "...because the design pulls more air than a filtered/baffled hood of the same [zero static pressure rated] cfm [when hanging unattached to anything in free air]." Ventahood use squirrel-cage blowers that also perform the function of baffle filters, thereby eliminating that cause of pressure loss. However, as blowers go, they are more susceptible to other pressure losses than conventional blowers, and hence if there is extensive ducting, or inadequate MUA, their flow rate will be less than the actual rate asserted.

My guess is that you should have a 24 x 42 inch hood aperture, requiring an actual 630 CFM obtained from a 900 - 1000 CFM rated blower. Read MUA related threads to determine how closely the interior air pressure has to match the exterior air pressure for safety. Your state may require heated MUA. There are a lot of ways to accomplish MUA under these conditions, and the threads here should help you understand what you have to tell us to allow better tailored help.

kas

From a health standpoint you want a proper hood and a proper powered/heated MUA for that range. @kaseki's calcs are spot on. (If you like to cook then I'd also suggest considering a Bluestar RNB range rather than Wolf.)

We are in the middle of a kitchen reno, and both the inspector (yesterday) and an HVAC company owner confirmed that our MUA does NOT need to be heated, or run through the central duct system. Definitely under 1K even with hiring an electrician to wire it. Husband is a GC so he can do some of it by himself. The inspector said that they are mainly concerned that we have dampers in both ends, and the same diameter going out and bringing air in...and their location of course. Check with your city inspector. My range would require at least 900 cfm, I went with 1200, and a 10" duct.

Unless you frequently have outside temps below about 20°f then you probably don't need it to be heated though some furnace mfr's won't warranty a heat exchanger if they find out there's below freezing air being brought in. The OP is in MN which definitely requires heating MUA.

"Definitely under 1K even with hiring an electrician to wire it."

I'm not sure how that's possible unless you're getting a lot of stuff for free. The blower and other parts alone will be over $1k at wholesale cost.

No need to attack my post, we found what works and passes for us...this forum makes points all the time that you must pay a fortune for MUA...we didn't need to.

I wasn't attacking your post (in fact I agreed with you on your comment about heated.), only asking how you did it for less than the wholesale costs of the parts. Which I'd still like to know.

A motorized makeup-air damper, pressure switch, transformer and whatever else...spring loaded roof cap...it wasn't 1K. This was ok for us, our house is not new/super tight, and has large open areas...this satisfies the local code, and was recommended by the hood vent manufacturer.

Our MUA isn't heated either. But we are in NC and it's not often we get temperatures below 20.