Don't do it!!! Compatibility aside, it's just not going to do what you expect it to do. I have a Dacor downdraft system and a Dacor gas cooktop and it's absolutely useless. It sucks the heat from the gas burners, and it's so noisy you can hardly hear yourself think. In the three years I've had it, I can count the times I've used it on one hand. I'm about to do a kitchen remodel, and I'm keeping the cooktop but ditching the downdraft. I'm still not sure if I can vent to the outside because the cooktop is in an island and I can't go straight up and out. But we're trying to figure out a way to vent up, sideways and then out. It'll require a few bends in the vent, and I have an HVAC person figuring it out for me. But I'd sooner have NO exhaust fan than re-install the Dacor downdraft.

humble-bee, We've got an elderly family member with an implanted ICD, and his doc said it would be wiser for him not to be around induction stoves until there have been more studies done testing the effects of close-range induction on medical devices. But I don't know any current data on it. It may prove to be quite safe. I'm not keen on induction myself, having always avoided living under power lines, cell phones, etc, but that's quite possibly an irrational fear. On the other hand, some folks are quite sensitive to the off-products of burning natural gas or propane. If you have a gas stove, you really need an externally venting range hood for health reasons. Our stove is a 1949 gas model with pilot lights and we adore it. We do have it checked out every year along with the dryer and furnace, just to make sure all the seals are ship-shape. In terms of stove preference, it's really ALL about what you're used to. Over the years this forum has seen more disputes over gas vs electric than Macs and PCs. I'm currently using a cheapo glass-top electric as we await our upcoming remodel, and I loathe the thing with the passion of 100,000 btus. It simply won't get clean, even with a razor blade. Blech.

Yes, some of us have no other options b/c of the design of out kitchen. I had an old Jenn-Air electric rrange w/ a downdraft in my "original" kitchen and was perfectly happy with it. I did lots and lots of research, attempted to change design to avoid downdraft and just could not seem to work around it and accomodate other priorities in the room. So.....we have a 6 burner Dacor gas (propane) cooktop. (36"). Installed a 36" Thermador downdraft. Chose this model b/c it rose higher than others and wanted one that would be taller than my tallest pot. The sales guy convinced me that a 600 cfm remote blower would be more than enough. I had plenty of conversations with him and the HVAC guys, talking about what I wanted, what I had learned, etc. The 600 cfm doesn't really seem like enough, we cook in our kitchen daily, often several times a day. I don't remember smells lingering like they do now, steam can hang around, and heaven forbid that we burn something, that fills the room for sure. Anyway, the bottom line is that if I had to go back and do it all again -- ideally, the design would not call for a downdraft. Can't undo that one - so, I might consider a different cooktop -- electric or induction. Finally, I would make sure that I have a blower powerful enough to handle what I am doing -- I think we should have gotten a stronger blower, and we still might. But for the time being I am learning to live with this and adjust our cooking accordingly. The Thermador has done its job to the best of its ability. I do like the additional height of 14" as opposed to most others which I believe are 8-10". I also wish that we had gone with the 1000 cfm inline blower rather than the 600. Here is a link that might be useful: Thermador downdraft

I would argue that it's not CO or CO2 that is your problem. Rather, it's the fundamental dilemma that the more effective your downdraft vent is, the less effective your range will be. As a prior owner of a (cheap) gas range with a downdraft vent, the biggest problem is that the minute I turned the vent on, about half of my BTU's got sucked out the vent. You could literally see pots come off a boil when I turned the vent on. And the times you would most desire to have a vent working--searing meat, for example, with all the smoke it produces--are the very times when you can't afford to lose BTU's down the vent. Yes, some higher end downdrafts, especially the ones that rise up 6'' or more above the range surface are less prone to this, but it's still a pretty poor compromise to me. I agree (as usual) with buehl that you'd be better served looking for creative ways to do a real hood, if you're really serious about cooking well.