Yes, duct free requires frequent filter changes (or cleanings), and they can be costly. I suugest you check with your retailer or Jenn Air customer service about the cost and frequency for the model you are looking at.

If you do vent, it must go outside. You certainly don't want all the grease building up in your crawl space.

I suspect the Jenn Air downdraft is more expensive that a regular cooktop - so make sure your consider that before you dismis other options as too expensive.

Also, you should be aware that downdrafts with gas cooktops tend to suck the flames sideways and away from the pots.

There are some very nice (not bulky) island hoods that offer a recirculating option and are not too expensive.

http://www.overstock.com/Home-Garden/Broan-Elite-30-inch-Chimney-Wall-Hood/3627742/product.html

http://www.ajmadison.com/cgi-bin/ajmadison/GXI6536DXS.html

One other thing I forgot to mention - the downdraft will probably take up most of the cabinet space below your cooktop.

A flush mounted downdraft is practically worthless particularly if you're not going to vent it. If you're not willing or able to go with an island hood or telescoping downdraft, I wouldn't bother with anything. Vents are not usually required to pass code in most locations.

You mean the duct free is worthless but it's okay as long as you vent it to the outside? Jenn Air claims to have the best performing ventilation system. I absolutely don't have the space for telescopic and really have no interest in an island hood. The previous owners used to have a pot rack and it was amazing how much larger and more open the kitchen has looked without it. I can't imagine how much more closed in a hood would make the kitchen. Plus, I have a 2 year old and I can just about bet money that he would climb up on the stool and be hanging off the hood in a heartbeat. Or, hit his head on it! If my cooktop was on a wall, I would do a custom cabinetry hood as I'm really not a fan of the stainless ones. I think they look too industrial but that's just me!

I don't think an unvented downdraft is worthless, but close to it. And certainly not worth giving up all the cabinet space underneath, especially in a small kitchen.

I've read the Jenn Air claims, and I think they're ridiculous. I tried to find out on what basis they made those claims and found nothing to substantiate them. I think they even claim that their downdraft is more effective than hoods which to me is just crazy. Smoke, flames, and steam all rise so how can that possibly be valid?

By the way, I've had a Jenn Air electric downdraft for 25 years and I rarely even use it. I do use it when I boil water for spaghetti, but most of the steam still escapes.

Sorry we're not giving you the reassurance you were seeking, but you asked.

That's okay. I've lived here for nearly 10 years without any cooktop ventilation and have fared okay. I don't do any indoor grilling, searing or stir fry but just wanted to be up to codes because it will catch up with me when we try and sell. And, the output on these burners (5,000 to 17,000) is higher than what we currently operate. I was mainly wondering if duct free was better than traditional but I gather it is not. If you've had a Jenn Air for 25 years then you must have had pretty good luck with it. I'm sure the newer ones have more efficient downdraft. This one claims to be 425 CFM.

Just to clarify my previous post, I believe that a flush mounted non-vented downdraft is completely worthless and a vented one is only marginally better - also it locks you into a Jenn-Air cooktop since they're the only one who makes such a thing. If you really won't put in a hood which is your best option, then I'd get whatever cooktop you want and skip the ventilation.

I think GE makes a downdraft flushmount vent and Kitchen Aid is about to come out with one, so there will be a few options besides Jenn Air. I guess Jenn Air was just the first maker to do this type of vent and they claim they are the best. I am pretty sure it's a codes violation to not have any type of vent and that's why I feel I must go with one and I for sure don't want a hood. So, I suppose I sort of am locked in with JA but is that such a bad thing? I am a little concerned over their higher than some repair rate but this is the only JA appliance I am using in the kitchen and so fingers crossed. I do like the looks of it though. Does anyone on this forum have experience with a recent Jenn Air downdraft or is the negativity towards them based mostly on hearsay or experience with older models?

Before you proceed, I seriously suggest you check on the building code for your area - I'd be really surprised if they require ventilation for a cooktop.

Though it isn't recent I had a JA range with the downdraft, vented outside. It was noisy and did very little. I then went with a Thermador range and Thermador telescope. It was a big improvement. Now I have an overhead hood and another greater improvement. If there is any way you could do a telescope with a good motor it would be worth it.

This is a bit long but I hope provides something..

I have had a Jenn Air down draft cook top for 8 years. I like the looks but the down draft system is poor. Much of the steam grease etc escapes into the room. I cook and fry a lot and I also paint the kitchen every other year. Fatty burgers on the grill, not the griddle, is a sure way to get the scare of your life. I cooked 6 ground chuck (80%lean) burgers once for a group and I had a flame that went over and down into the duct. Sounded exactly like a jet engine and look similar. Don't do it!
I did buy a magnetic floor heating duct attachment, the ones from plastic that directs the heat 90 degrees and I use that with the J/A to concentrate the draw of the duct from the side I am cooking from. That made a big difference. It also stopped the a/c vent from over powering the J/A duct and blowing steam etc into the kitchen. The down draft is a cool idea but poor performer. Beats me why Jen Air keeps it up. Not to mention their prices are ridiculous as their down draft claims. I love the modular idea...but get a overhead vent or none.... you can always paint. Oh!...Don't forget the makeup air needed. For every cubic foot of conditioned air you down draft outside....you have to pull in air from somewhere to replace it..like through leaky doors and windows etc.

I know this is an Old Thread, but I honestly believe it deserves some added input. The Jenn-Air unit you mentioned and also the slide-in range with down-draft are both excellent. The ductless attachment does work well,and the filter is somewhat expensive, around $50, but generally needs replacement only every 6 months if you use the grill on a regular basis, and less if you grill less.
Part Numbers: Duct-Free Install Kit JDA7000WX or W10620783 for the kit; The Duct-Free HAPA Filter is # W10177003 . With the Jenn-Air yopu will find they have discontinued many wonderful adaptations for the unit, but they are often available on eBay and at greatly reduced cost.

Eaglewerks - do you currently own a downdraft ventilation system?

Im in the process of building a new home and my kitchen island will have my thermador silver mirrored finish induction cooktop for which I am planning on getting a telescoping downdraft ventilation system.

Looking for advice on best (I recognize everyone says they are horrible) downdraft to purchase. I personally use my current hood for its light and in my entire 42 years have only used the fan a handful of time.