Wow! A rare case where the aesthetics part of the performance-aesthetics-economy: pick-any-two limitation is not a factor in hood selection. But first, given a sealed household, I would strongly recommend obtaining a furnace kit to use outside air. This will avoid the possibility of the MUA system not working perfectly and the hood causing negative house pressure and hence backdrafting of the combustion appliance. I know that such devices exist for Beckett burners, and would guess that there are adapters for other burners. As the OP correctly notes, a 200 cfm ERV is not going to cope with a 1200 cfm vent hood. (Actually, what would happen with a sealed house is that at full power, the hood would pull the cfm the ERV would let through into the now minus a couple of inches w.c. house pressure.) So MUA is essential, and in the mid-Atlantic region would be pretty uncomfortable in winter if unheated. Depending on one's tolerance for heat and humidity, cooling in summer might be optional or not. We are starting to get into the realm where performance-economy, pick any two is applicable. MUA can be roughly characterized as passive or active. By passive is meant no fan in the circuit. Active uses a booster fan to keep the house pressure stable. No-fan only works for simple ducting with a vent hood air flow controlled damper. (A recent post here provided some sources for these.) If a filter is used at 1200 cfm (or whatever flow actually could be pulled with all the doors and windows open, then the house pressure will drop. One can see on websites selling filter packs that the pressure drop at such flow rates is too large for combustion appliance safety, which require negative pressures not be greater than 0.03 to 0.06 inches depending on appliance type. Active is needed to overcome the filter restriction. It may be needed to overcome heating heat exchanger restriction and/or air conditioning heat exchanger (expander) restriction. The difficulty with active is balancing the MUA air flow rate against the variable hood flow rate such that the house pressure is near zero. This usually requires a control system of some sort, and can be a "project." What to do? What to do? Only one free-of-processing-controllers active MUA has occurred to me. In the simplest embodiment, the hood control is connected to two parallel wired identical fans, one in the hood exhaust path and one in the MUA path. Then the two will (try to) operate at nearly the same flow rate at every control setting, and one only needs to adjust the MUA duct restriction until it matches that of the hood path. More exactly, adjust the MUA path so that house pressure falls very little as the hood is turned on. Note that this doesn't account for bathroom fans, fireplaces, or other exhaust flows not due to the hood. In such cases, PID control of the MUA fan would be needed. In my case, due to a 1500 cfm hood, 1000 cfm over-oven vent, fireplace, and three bathroom fan household, I am building an active MUA that will use an axial blower in the 2000 cfm regime. It has to overcome the pressure loss of its intake vent, its filter, and its heat exchanger (which is hot water pumped from my oil burner). Control is via a Fuji PID controller operating from a BAPF differential pressure sensor. The motor power control is not yet selected, and a lot of sheet metal action is still needed, along with further attic revisions that I seem to have trouble getting to at the needed rate. I recommend the OP and/or his HVAC person read the "Kitchen Ventilation Systems Application & Design Guide" that may be found at Greenheck's web site. It periodically moves around, URL-wise, so a Google search by name may be fastest. Greenheck or one of its competitors may be able to provide what you need for considerably less agony than a do-it-yourself HVAC project would. kas

Any time the flow of air (or part of the air) has to change its velocity vector (direction and/or speed), even slightly, work is done on the air, and this requires either heating or force times distance. Pressure is force over area. Velocity change occurs not only when a duct bends, but when there is turbulence in the duct or at the duct walls, or when the air is forced through a filter, around baffles, etc. Thus, there are many ways that pressure drops occur along a flow path. If not, one could blow through a straw without having to build up pressure in one's mouth. I use a large (three-foot-square) vaned ceiling diffuser to introduce MUA into a hallway adjunct to the kitchen. The diffuser is about 18 feet from the edge of the hood. This configuration was the best option relative to where I could take the air from the roof area. It is my expectation that by the time the air gets to the vicinity of the hood it is flowing relatively smoothly and low in velocity due to the size and length of the hall. Certainly other approaches would work for other kitchens depending on where the air is taken from and how a house is architected. Test kitchens use a porous diffuser panel in an adjacent wall to the hood under test. I am sure that from a functional point of view, MUA flowing out from enough toe-kick area would also work, so long as it wasn't somehow directed at the stove. For example, if a cooktop were on an island, and the entire toe-kick area were grilled using a set of registers, the MUA would flow out and then up in a way that did not disturb the rising effluent from the pans. Even down flow behind a refrigerator can work if the path behind and underneath the refrigerator is relatively open (several times the area of the supplying duct.) Never forget that perfect is the enemy of good enough, and what we are trying to accomplish is good enough capture of grease, moisture, and odor. Good enough is also user dependent, so not everyone needs to put up with the compromises that a nearly perfect MUA system would impose on a house. So, my best advice is to find a way to introduce the air that doesn't blow at the cooking zone and disturb the natural rise of the cooking effluent. kas

I can't answer most of your questions because I don't have any of your designated parts (other than an LD10 silencer). I may have some of the others in the future. CaptiveAire may only do commercial. There is a CaptiveAire hood with what appears to be MUA attached at a glorified hamburger joint in Concord NH. I haven't been right up close to it, but it seemed quiet. With commercial systems, one can get whatever CFM one wants. Also, they usually keep the customer area (not relevant in this case) at higher pressure than the kitchen area. In the image below (from Greenheck's eminently worth reading guide at http://www.greenheck.com/media/pdf/otherinfo/KVSApplDesign_catalog.pdf ) the MUA appears to be dumping into a perforated ceiling. With respect to your parts combination, however, it looks to me like overkill. The listed insert baffle space appears to be approximately 4 ft x 1 ft, so only 4 square ft entry aperture. At 90 CFM per square foot, that is only 360 CFM required. Scale up depending on various losses and considering that a blown MUA is present, then you couldn't need a blower rated more than 1.5X that, or 540 CFM. Your listed one is specified at 1936 CFM. (I didn't search out the fan curve.) I'd choose that to go with a hood having an entry aperture of 14 sq. ft., e.g., 7 ft x 2 ft, or 6 ft x 28 inches. The actual in situ flow of this impressive blower is likely to be around 1300 CFM. Now, I'm not familiar with your intended range, or how it is configured, or your kitchen layout, but if the range is 4 ft, then ideally a larger than 4 ft insert/hood is called for unless you have deep side cabinets or side curtains on the hood. You are on the right parts trail, only the sizes need to be better tailored for what you intend. In other words, grow the hood or scale down the air transport parts. So please report your stove cooktop dimensions, your intended height to the hood or hood insert, and any restrictions on how large your hood can be. With respect to MUA via toe kick, someone here reported a problem with the air moving across the floor to a nearby cabinet section and rising close to the range, thereby disrupting the plume flow. If toe kick insertion is best for you, try to choose a toe kick area that requires the air to move a significant distance in the room in getting to the hood. Also, the toe kick area needs to be commensurate with the hood area, or you will need a more powerful MUA blower than hood blower to overcome the pressure loss at the toe kick registers/diffusers.

Awesome. Connecting with the AC system is not something I like either. A few questions: 1) I am buying a Miele cooktop and Hood (this one), because I have an open space and we often forget to turn on the hood until it gets all foggy. Since they are wirelessly connected, hood will turn on when cooktop turns on. This is to say I don't wanna change the brand. Can I use the Fantech make-up-air system with Miele? 2) Which damper should I pick? My Hvac guys said that he can go with a gravity (aka atmospheric) damper, and he quoted me the system for $400. Would that be a good option? I am afraid that damper would open also when mild negative pressures are created when the AC/heat system is on, and we are back to square one, I might as well have added the make up air duct to the AC duct. The other option would be to have an automatic damper, that automatically opens when the hood starts and close when the hood stops. That would require some wired connection with the Miele hood. Is that even possible? Should I just go for gravity damper then? 3) See below a picture of my old kitchen, and the pic with the model of the new kitchen (it does not have the hood yet but it will go above the cooktop). Where would you put the opening for the make up air system. I also thought that "introducing make-up air in proximity to the range/cooktop vent hood (but not so close as to interfere with normal air flow) eliminates the need for conditioning the make up air", as you said. Which do you think is the best spot in my design? I just don't wanna have a draft of cold (40-45 F) air hitting my head/back when cooking, or hitting my lady or guests who usually sit on the stool in front of the cooktop so we chat and have a drink while I cook. Should I put it in front of the left most pantry? Or maybe just on the left of the island?