Hi Texas Gal, My hood is the RA0236SQB-1 model, a chimney-style that seems to be phased out in favor of a newer model. Overall, I'm very happy with it, although it may not mean much as prior to installing it last April I had no active ventilation in my kitchen. After the rotary switches failed and were replaced (within the warranty window), there has been no issue with this hood. I also don't expect any, as it's a simple, mechanical appliance, a fan driven by a brush-less AC motor installed in a steel box. Having sad this, I think that you're looking at a different hood: http://www.koberangehoods.com/product/RA-028SQB-WM-1.html. If that's right, then you're talking about a different animal. The depth is only 19.5", which means poor effluent capture. The baffles look different too and I couldn't find a picture showing the underside so it's not obvious how much is covered by baffles. Did you look at the CH-122SQB-1 model? At least it's 22" deep. Cheers, P.S. How does one send private email via gardenweb?

My understanding is that HRVs are intended to provide a modest change in interior air while capturing back some of the heat that would otherwise be lost through air exchange. Typically, they are not scaled for 600 - 1600 cfm flow rates, but I don't know what yours is designed to do. If your house were perfectly sealed, the flow up the kitchen vent would equal the flow in through the HRV. This might be only 200 cfm even though your kitchen vent blower was rated for 1200 cfm. In other words, the HRV may be too restrictive for the flow rate you want. This leads to requiring a larger duct that opens only when there is significant vent flow. (This part is easy.) But still, the house pressure may drop too low. Problem 1: For safety with any combustion appliances in the house that are not separately supplied with air, or fireplaces that are almost always connected to the kitchen pressure, the house pressure cannot be allowed to become more than slightly negative. This may force the MUA system to be an active system with a blower. Problem 2: When you need to heat and/or filter the MUA, then there is yet more restriction and it may again be necessary to provide a blower in the MUA duct. Problem 3: Controlling this blower so that it works correctly for any cooktop vent flow rate, bathroom fan flow rate, window condition, fireplace operation, etc. leads to a complex design. The least complex design I can imagine for a high flow rate kitchen hood has these characteristics. a) All combustion appliances have their own MUA (and no chimneys leak). b) No fireplaces are used when the kitchen vent is on. c) A large duct (at least equal to the one above the vent hood) with damper is used to bring in MUA, and the damper is controlled by a hood duct flow switch d) If heating is needed, an electrical resistance grid that causes minimal pressure loss is used in the MUA duct, controlled by a thermostat. (The power requirement may be significant, at least for the period of high ventilation cooking.) e) If it is hot in the summer you have to lump it. All other approaches of which I am aware will have additional complexities and costs. MUA induced into the hood will not work well and doesn't in most commercial settings. Use of water-to-air heat exchangers, or refrigeration-to-air heat exchangers (heating or cooling) in the MUA duct will cause enough restriction that the house pressure will become too low or little MUA will flow, mandating an in-line blower and its control system. Fin type heat exchangers will also require quality air filtering for further pressure loss and bigger compensating blower. kas

Thank you for the responses... Let me answer some of the follow-up... The hood is only moving a small amount of air (measured at approx 200CFM above the stove halfway to the roof in the new 10" ducting. So, it is moving a small amount of air, but nowhere near the 1200CFM that it is rated at. There damper above the stove is not blocked or sticking, so that isn't the issue either. I'm not an expert in centrifugal fans, but everything I can find is that is should spin in one direction for it to operate correctly. However, if it spins/operates in the wrong direction, it will still move a small amount of air, which is what mine seems to be doing. In regards to the fan itself, it just plugs into the actual hood, so I'm not sure it is wired improperly. I'm guessing it could have been manufactured incorrectly? Has anyone ever seen one of these fans operating in the wrong direction? Thank you again for the comments.

I purchased my Viking cook top, oven and microwave nine years ago. The cook top lettering decals came off twice in about the first 18 months and the whole cook top needed to be replaced each time. Whole decals literally came off on my hand as I was cleaning it. A Google search showed that several other people had the same issue. I was told that I needed to be careful and not to use any stainless steel cleaners, etc. when cleaning the appliances. Since then I use nothing but a damp cloth and when grease is an issue I add a tiny bit of dish soap. After the last replacement the number decals have remained on the cook top. I do like the way the cook top functions. The oven had problems right out of the gate and needed tweaking and then replacement. I was very careful while cleaning my oven so by the time the oven numbers started to come off it was too late to be covered by warranty. I inquired about purchasing new decals from Viking and was informed that wasn't an option. While some of the markings remain, others are made with a Sharpee. Very high-end and precise, don't you think? The oven tends to run hot so I need to keep an oven thermometer handy. So far the microwave has been fine (although my old GE did a much better job with popcorn) but this last week the door has been balking when I try to open it. We'll see what happens next. While Viking covered the cost of the replacements during the warranty phase, we had to pay the cost of labor. That was not an inconsequential expense. The second repair guy messed up the retractable vent behind the cook top and the oven guy messed up the protective metal cabinet shield that my contractor installed on my cabinets. I must say the appliances work well but I won't be buying Viking when I need to replace them.