How about:

• Whirlpool WVW73UC6LS 36 in. 300 CFM Chimney Wall Mount Range Hood
• GE JVW5361SJSS 36 in. Convertible Wall-Mount Range Hood
• Falmec Potenza FPAFR36W3SS Afrodite Wall Mount Range Hood with 3-Speed/280 CFM Motor
• Sirius Wall Series SUE336 Wall Mount Chimney Range Hood with 295 CFM Internal Blower

There’s a big difference between having a high-powered, professional gas range and having an induction cooktop made for home use. I would be surprised if you need MUA.

There are three ways to do the math. Assuming the cooktop and hood are mounted against a wall, you want a minimum of 100 CFM per linear foot.

36/12*100 = 300 CFM

The other way to calculate uses BTU. Divide BTU by 100.

10,000 BTU/100 = 100 CFM

The last calculation involves the cycling of air in the room over 15 minutes, so you would multiply room dimensions (length x width x height) and divide by 4 and get a number.

(ft cubed)/4 = CFM

When you complete these calculations, the biggest number is your minimum CFM. I never did the last calculation when I bought my insert in part because the room is huge, open to the sunroom and family room (and almost every other room in the house), and I knew 300 was an upgrade over the hood I am replacing (200 CFM), which in itself was actually fine. I used my best judgement and chose a 300 CFM insert. I hope this helps.

I should also mention ducting. I have a 7” rigid round vent that remains 7” all the way out of the house, travels a short distance (total of 6 feet perhaps) and has 2 90 degree bends (one to go up, and one to go out. Ducting matters a lot. No matter how many CFM your fan can move, it will not move air at a faster rate than your ducting can accomodate. Also, use of flexible ducting is not recommended.

The commercial cooking lineal-foot algorithm is supposed to include the end lengths if they aren't curtained. Note that this is for commercial hoods with very large internal containment volumes before the typically high baffles. Residential hoods have little volume below the baffles and need higher flow at the baffles since there is no averaging over the baffle space. The commercial cooking BTUh algorithm should be superseded by the Greenheck specific flow rate algorithm. See: https://www.tagengineering.ca/wp-content/uploads/2015/02/KVSApplDesign_catalog.pdf. Containment volume is also relevant here.

Room air cycling completely misses the point that the air flow into the hood baffles has to be high enough in velocity to assure that no upward rising cooking plume portions that are captured by the hood overlap of the cooking zone escape the hood, typically by sheet metal reflection of the plume components making use of conservation of momentum.

An actual 90 ft/min should be sufficient for most residential cooking, including stir fry and searing. It won't be fully successful if there is not sufficient hood entry area overlap of the expanding plumes. 90 ft/min corresponds to 90 CFM per square foot of entry aperture.

In all cases, the calculated flow rate (CFM) has to be achieved in spite of the pressure losses in the baffles, hood transitions, ducting, cap (if not an external blower) and the make-up air (MUA) system. A rough estimate of pressure loss effects on typical blower fan curves given adequate MUA would be that the actual CFM will be only 2/3 that of the blower rating, so equivalently, the calculated CFM required should be multiplied by 1.5 to yield the rated CFM of the blower.

“An actual 90 ft/min should be sufficient for most residential cooking, including stir fry and searing. It won't be fully successful if there is not sufficient hood entry area overlap of the expanding plumes.”

Yay! So 300 CFM should be more than enough, overlap and ducting permitting.

@eam44: I think your math needs refreshment. ft/min gets to CFM via multiplying by sq. ft.

• 300 rated CFM ==> 200 actual CFM will support a 2.2 sq. ft. entry aperture at 90 ft/min.
• 300 actual CFM ==> 450 rated CFM will support a 3.3 sq. ft. entry aperture at 90 ft/min.

Both of these are too small for a 36-inch wide cooktop, which should have in the vicinity of a 42 x 20-inch (5.8 sq. ft.) hood entry aperture (if wall mount).

One can argue for more modest cooking conditions for some diets, and in these cases I would not go lower than 60 ft/min, and then only with induction, and I would still assert cooktop overlap is required. So more than a 300 CFM rated hood would still be required with a hood capable of full capture over all the potential pan areas.

Alternatively, if one wants to risk no deliberate MUA, and can live with pulling air through wall cracks and doesn't have any combustion appliances connected to kitchen air while still staying below the rated 300 CFM code requirement, then a less deep but still 42-inches wide hood could be considered, so long as all greasy cooking is performed on the back hobs.

Induction needs the exact same ventilation as gas. Unless all you do is boil water. You still need to remove the effluent from cooking.

Realistically you'll need mechanical MUA and you also want that for your health.