I’m installing a kitchen for my grandmother right now who is on somewhat of a fixed income. She will be getting a 30 electric cooktop that backs up to a half wall (approx 48″ high) with the dining room on the other side. There will be a small 8″-12″ “back splash” behind the cook top. She really hasn’t found a cooktop with built in downdraft that she likes, and most of the stand alone pop ups are too expensive for this job. I’m thinking about using an exterior mounted fan ducted with flat 3.25″x12″ steel duct that is connected to a vent in the back splash and controlling it with a variable speed switch. I know that I’ll have to convert to a round duct before the fan which is fine. I’ll probably do that as soon as it exits the wall into the basement. I think that the corners of the rectangle duct will be places for grease to land. I can vent to exterior in about 8′-10′ with as little a three elbows. I was thinking something along the lines of 400 cfm but I’m open to going bigger. I don’t want to oversize it because of the fireplace issue. The problem I’m having is finding a similar installation that has been proven, and also finding some kind of grease filter that will fit into a vent in the back splash. I can make a vent cover from corian to match the counters, so custom sizing that won’t be a problem. Does anyone see a problem with buying something off the shelf and cutting it to the size I need? Any feed back or potential problems that you guys can come up with would be greatly appreciated.
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your biggest challenge will probably be the grease filters...and convincing an inspector that a non UL listed assembly is OK......
Bumb....
We are considering the same venting system because I don't like how visually prodominate a vent hood can be......
Have you fully researched the pop up vents? I agree that most of the built into the cooktop ones are not great, but we have the 30" Jenn-Air and it is ok. Not great, but ok.
The pop-ups are somewhat expensive, but there are ones not a whole lot more than the extra cost of a built in. You just have to make sure you have the space for it.
They are U.L. listed and designed for the situation.
I did a fair amount of research on the pop ups, and it never really occured that it may not fit. the cook top is 21 3/8" deep from front to back and will be going into a standard 24" base cabinet. subtract 1 1/2" for the 3/4" front and back and that leaves only 1 1/8" for something in the countertop. Besides that, If I'm going ot spend approx $300 on the remote fan for the pop up and then another $400 for the unit itself, thats already more than I would like to spend. I think that i can safely accomplish the same thing doing it the way I described.
Perhaps you don't spend much time in front of the stove cooking. Or maybe you do and someone else cleans up after you. Whatever, you're clueless about the need to clean the vaporized grease off of the air grill.
Furthermore, a 400 CFM motor (even a remote mount) will pull a lot of air, making a lot of air noise, especially with the convoluted change in duct work. You'll need a 7' duct to equal the same capacity of the 3.5 x 12. Using a 6" will cause the air to move slower in the retangular area, causing more grease precipitation.
Look overhead. Someway there's another way to make this work.
Edited 10/3/2006 1:33 pm ET by peteshlagor
Clueless huh.... maybe thats why I asked the question in the first place. thanks for the feed back or lack there of. And how does a pop up or even an over head hood magically eliminate this vaporized grease?
They has filters. Washable filters.
And the filters commonly fit rather tight.
thats why one of my questions was about the filters. Whats to stop me from using a pre made one from another unit in my set up? Even if i have to cut it to fit. The only purpose I see for the metal frame around the filters it to make them fit into a standard hood.
You're in a tight spot in more ways than one.
Is this just a cooktop, or a range unit (cooktop & oven)?
You really ought to check around the appliance guys for the Jenn-air 30" d/d cooktop; they can be very reasonable in price compared to a 'regular' cooktop and a separate fan/exhaust system.
Please, please, go back to the kitchen design, and see if you can get a 26" or 27" deep cabinet in there--there are few things tougher than getting exactly 24" of cooktop, vent, gas lines, electrical conduit (and BX/MC pigtails) and cabinet casework into exactly 24" of depth (which always seems to be 23 7/8").
If the depth will be an issue, consider a bit more width and add pilasters to the front corners to 'buy' you some extra countertop depth, if nothing else (a "stepped out" front can help, too, between the pilasters).
I've been to this game a time or two, and while it can be elegant, it almost always wants a shoehorn and a long lever to get it done (and buying that extra effort saves you no money, in a classic catch-22).
I've seen a custom-made exhaust using a half-wall behind a range install that looked good. Mind you, the 27 x 3" slot vent probably was a giagantic budget buster. So, I know it can be done, and done well. I'm just not certain it can be done well and inexpensively, too. I could be wrong, it's happened before.Occupational hazard of my occupation not being around (sorry Bubba)
It's just a simple 4 burner electric cook top, not a range or a cook top with an oven below. I don't need a gas line, and there is plenty of room for a conduit. I would go with a downdraft range, but she found one she likes already, and once she has something set in her mind, it's not easy to change it. Unfortunately the cabinets are already ordered and it's much too late to change one now. I could bump it out if I need to, but I think if I can get the vent into the half wall, I'll be fine. I'll be able to fabricate the custom sized vent from the left over corian from the counter tops, so i'm not to worried about that yet.
I don't need a gas line
LoL! That's usually when you find one right in the least best place to be most in the way . . .
Having wrestled most of the major dd/ brands in at least once, any "cheat" you can get the front of the cooktop cabinet out will help. I've quartered a newel post to hide the transition middling succesfully--but a pilaster on a face frame extension still works best when you absolutely must have that last extra inch.Occupational hazard of my occupation not being around (sorry Bubba)
I must be missing something. I'm using an electric cooktop. No gas.
I must be missing something. I'm using an electric cooktop. No gas.
That would be a good thing <g>.
Last time I did a "simple" here, let's swap the electric c/t for another, we discovered an (abandonded) gas line exactly where we needed to pipe the d/d ductwork (naturally). Or the time we did some apartment remodels, and the kitchens had all been plumbed for gas, and covered over in a previous (hack) renovation. (Some of the lines had not been capped in that 'renovation,' relying entirely on the cutoff at the gas meter . . . )Occupational hazard of my occupation not being around (sorry Bubba)
I gotcha. I couldn't figure out why everyone kept mentioning a gas pipe. This is going in a spot where there is currently just a base cabinet. The kitchen has a 30 year old range with sliding cook top with a top and bottom oven. the new kitchen will have a electric cooktop and a seperate double wall oven.
An option to consider.
Open two stud spaces behind where the appliance will be located, in each stud space (assuming 2x4 construction) use a 3-1/4x14 wall stack. Combined these are good for close to 400cfm, (1) 3-1/4x12 duct is good for only 150 cfm, btw. Also, 300 to 400 cfm for a standard 4 burner residential electric range is more than enough exhaust. More than 400 is not recommended. Use a 34"x12" grille mounted on the wall in a "plaster frame" across the two wall stacks. You can buy aluminum mesh filters that easily removeable (as would be the grille) for cleaning. Install a in-line cabinet fan in the basement (if this is slab on grade you're SOL) and discharge out a 10" round duct with a wall cap or small louver. Depending on the specifics of the structure, grade, etc., you may have to alter the discharge somewhat. You should pitch the duct to drain out the louver if possible. Grease filters, unless she does a lot of frying, are really optional.
Thats what i wanted to hear. I have no problem with using the two stud bays. Infact, I could easily remove one stud and just sking the wall with plywood to accept the sheet rock since it's only a half wall. Then I can pan of the entire area and route it into the basement below. Would it be bad to use something like thermopan for lineing hte stud bays? Or will the exhaust be too hot for it? Also, if 400 cfm is the maximum, what would you recommend as a good range for a single 4 burner electric cooktop?
Panning of stud spaces for use as return of room air is a marginally acceptable practice, in my opinion, and prohibited in some jurisdictions. For exhaust, not a good idea whether legal or not. The exhaust stream will not be too hot, rarely if ever exceeding 100 degrees (my swag). Depending on the cook, more often than not the exhaust will be water vapor from a boiling or simmering pot(s). Not something you want collecting or impinging on exposed studs. Even if you lined the three sides in the stud space and then panned over it, not the best configuration for an occassionally damp exhaust stream. I would recommend that you stick with complete ducts that fit within the stud spaces, with as few joints as possible. Wall stacks are readlily available in the sizes mentioned and the install will go faster. Also, once the wall stacks are in the basements, standard 90 degree boot fittings are available for common wall stack sizes as well. Adapting two into one and connecting to the fan will require some "field engineering". If you keep the stud in the middle, you may want to wrap a piece of galvanized sheet metal over it where exhaust will impinge on it.
I am just an HVAC design engineer. I don't know squat about what might be a good electric range, just how much heat I can expect from it. You may want to post this question on the CooksTalk forum.