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Advice please on range insert for wood hood!!

4 years ago

What is the quietest most reliable brand of range vent hood inserts for a custom made wood hood?
It will be over a 36” Cafe electric cooktop. Too many choices and not enough time to do thorough research. Please help! Thank you!

Comments (7)

  • 4 years ago

    You need a 42”-48 wide hood for that. Get a Ventahood brand. Plus the separate code required make up air system.

  • 4 years ago

    Thank you, Verbo. Do you know if Ventahood brands are quiet or have a sone rating? Also, for a 36" glasstop electric range, I don't know what size CFM I would need? I like the Ventahood reviews. When I look up noise rating Kobe keeps coming up and I don't know if they are reliable etc.? I have a Cochlear Implant and need something as quiet as possible to not interfere with my ability to hear.

  • 4 years ago

    Most quiet requires a quiet blower on the roof (probably an under-driven commercial up-blast blower or maybe an in-line blower in an attic, and a silencer between the blower and the hood. Some recent VaH hoods have been reported here as quiet.

    CFM requirements are determined by the temperature of the cooking oil generating the cooking plume along with the vigor (quantity) of plume generation. Not less than 60 CFM/sq. ft. of hood entry area is advised. Wok cooking and meat searing may require 90 CFM/sq. ft., and even then it is possible to overpower a given hood.

    You may regret not taking the time to review the many hood and MUA threads here for understanding of what the requirements are.

  • 4 years ago

    @kaseki thank you for the input. I have been trying to educate myself but it can be very confusing. I will be using an insert in a custom wood hood. It will be over a 36" cafe Electric cooktop so there won't be gas. More than likely the insert will be an internal blower built in the insert. I will be discussing an internal blower in the duct work, but it won't be external. I realize the external blower would be the quietest but it is not an option. So now that I understand more after taking your advice and reviewing threads, I will rephrase my questions.

    1. What brands could be recommended that would be quiet and reliable for an insert with a built-in internal motor inside the insert?

    2. If I am cooking on a 36" electric cooktop, how many CFM would I need or does it make a difference if it is electric or gas? We are not wok cookers nor do a lot of frying inside. We will have an outdoor kitchen for heavy cooking and grilling but I would think it would be a better choice to get a multispeed with variable CFM options in case we should need it? We do have an open concept kitchen with 10' Ceilings.

    3. Should I make sure to use a vent insert that will call for 8" duct pipe? I noticed many of the lower CFM come with 6" duct and I think I understand that will make it perform less adequately and be louder. The range top is on an internal wall and can be ducted straight up through the 10' ceiling through the attic. The house is one story but a second floor can be added in the future and would have 9' ceilings so it is a longer run of duct to reach the roof.

    Thank you for your input. It has been very helpful. I could really use some help deciding these factors and then a brand that will be suitable. Noise is a huge factor and I need something as quiet as I can get with the conditions that will be applied.




  • 4 years ago

    Due to force majeure, I won't be able to address this until later today.

  • 4 years ago

    First and foremost, adequate capture area is necessary. This means overlapping the likely array of cooking pots and pans by enough that cooking plumes expanding from the cooking surfaces at 10 degrees from vertical are captures. Typically, 6 inches wider than the cooktop is necessary for hood heights of 30 to 36 inches above the cooktop. Front to back calls for 24 inches or so, but if one limits greasy and/or odoriferous cooking to back burners, depth to the range edge may do. Looking at the 2021 Wolf design guide that I conveniently have, the largest insert is 22-5/8 deep, of which some portion is light bar, so it is not going to have much overlap for the front burners. You would probably use the 40-3/8 wide unit in a 42 inch cabinet.

    This particular hood, counting the light bar as wall hoods have some capture at the front, has a nominal entry aperture of 6.3 sq. ft. At 90 CFM/sq. ft. for good containment, one needs 570 actual CFM, which might require a 900 CFM rated blower. If you insist on an internal blower, then for this particular Wolf hood example, 600, 800, and 1200 CFM internal blowers are available.

    Hoods at full power are not typically quiet, but some are conversationally quiet enough.

    Maybe 800 (with actual 500 CFM) will be sufficient for your cooking. With a 1200 CFM rated blower always run at partial power, you may have less noise than the 800 run at full power.

    In my experience, Wolf (Broan) blowers use induction motors that can be continuously variably controlled, but this should be checked for any particular combination. You can, of course, have whatever you want custom built by ModernAire.

    Duct size should allow the actual flow rate to cause no more than 2000 ft/min air speed (from the actual, not rated, blower CFM) in the duct to avoid grease collection from impingement. In general this will require an 8 or 10 inch duct depending on blower selection. Lower velocity is quieter, but less than 1000 ft/min may lead to grease collection by condensation unless operating the hood before generating grease is sufficient to heat the hood above the dew point of the moisture in the cooking plume.

    I prefer baffle centrifugal impingement filtered hoods over blower centrifugal impingement hoods (VaH "Magic Lung" types). In your case where the ducting may reach 20 ft or more, and you haven't yet determined the MUA approach, I would use a blower more resistant to pressure loss than the VaH squirrel cage designs. If you were on an external wall dumping the hood directly out, the VaH would not be affected by duct length, only MUA limitations, yet to be addressed.

    Most places in the USA with temperate weather require make-up air, and this means at a minimum a lightly filtered duct from the exterior to a point where the air can reach the kitchen. It may call for a ceiling diffuser, heater, and maybe a blower. The duct path needs to be considered. Risk of back-drafting combustion appliances needs to be considered. You have a way to go here before you can say you have a plan.

  • 4 years ago

    Thank you very much for all the info. I definitely have a way to go but your input has been very helpful and greatly appreciated.