range hood confusion

Question

I am making some changes in a somewhat older kitchen. Part of this is replacing the stove with a 30" dual fuel (LP) range but keeping the existing 300 CFM fan. I was all set to buy a professional stove-either Wolf or Miele but I have been told my hood will not work. The existing hood is a under the cabinet range hood that vents to the outside. The duct is 3 1/4 x 10"...the opening butts up against the roof line-(it is a A frame home) so it is difficult to change it without major work. Is it true I could have problems? Note this is a second home and not much cooking is done there on a regular basis and even when it is all 4 or 5 burners (depending on the stove) would seldom be used at the same time. I appreciate any info.

Answer 1

Clarification on the question may change this, but I took a look at the Wolf "Ventilation Guide" on their site, and it does recommend their PRO hoods for the dual fuel ranges. The 36" model calls for a 900CFM hood, but for the introduction to the page it says:

Ventilation performance is measured in cubic feet per minute, or CFM. The chart below provides CFM suggestions specific to the Wolf cooking appliance and ventilation system used.

Now the use of the word suggestions tells me that these are not hard requirements. Another section of the manual has this to say:

The appropriate airflow capacity is determined by the cooking space and cooking style. ... Greater exhaust capacity is required to handle the moisture generated by boiling large pots of water or the grease and smoke from grilling or frying. Cooking with high heat or cooking aromatic foods may require additional CFM and increasing the capture area...

That shows that they can't possibly give you a hard requirement because the variables are all usage related and also depend on the space the range is going to be set in.

These luxury brands also live on customer experience, so if anything they are going to pad any requirements to make sure they meet expectations. You don't want someone spending $15,000 on a stove to complain to their friends when the boiling spaghetti pot steams up the kitchen.

So, I say get the best hood that you can, but if you're not going to do much cooking, 300CFM will be fine. If you do end up hosting a party and the stove goes into overdrive, you might get more odor or moisture than you would like.

Answer 2

Don’t know why question showed up on the active discussion list, but this my answer to the OP question and other comments. This is too late for OP decision point, but will provide a viewpoint based on the comments posted and JPhi1618 answer.

The original size of the duct work is adequate for the high capacity range hood, which was the OP real concern. .
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JPhi1610 is right on with ” You don't want someone spending $15,000 on a stove to complain to their friends when the boiling spaghetti pot steams up the kitchen.” or why is it so noisy.

1. A commercial stove generates a lot more heat per burner. A large pot of water will start steaming in 1/3 the time of a home stove. On high, the commercial stove will be generating a tremendous amount of steam compared to the home stove.

2. The large fan will run at a lower speed to move the same amount of air with less noise. The commercial hood will have the capacity to move the grease, steam, odor, etc. when the stove is operated at full capacity.
   

3. With the 300 cfm fan, you would be running on high most of the time creating a lot more noise when compared to the high capacity fan.
   
   When spending 10-15K for a high end commercial range, you will not want to regret a decision of not having upgraded the hood to match the stove capability.