Hi all, I have some questions to ask current ARS users, due to the specific configuration of our stove area--it's not atypical, but it seems to be suboptimal for any of the ARS hoods' guidelines. Specifically, we plan to replace a hood/microwave hybrid that the previous owner (a flipper) installed over a 30" electric stove. The cooking space (i.e. the height of the area between the cooktop and the bottom of the hood/microwave) is 20", and the microwave itself is 15.5", and the microwave is mounted on a cabinet that's about 17" tall. However, since VAH's guideline suggests the cookspace should be 20-24" tall, installing the under-counter ARS hoods (PRAH6/SLAH6) directly under the cabinet would make the cooking space about 5.5" taller (29.5") than what's recommended. But the specs seem to imply the 30" wall-mount models use a 7' duct for all the filtration media, and our kitchen doesn't have that much clearance (the height between the bottom of the microwave to the ceiling is less than 5'). My questions for ARS owners are: Is the suction still acceptable if the clearance between the cooktop and the hood is 30" (instead of the 20"-24" recommended by the specs)? How likely an under-counter ARS (PRAH6/SLAH6) can be mounted on the wall? Can the wall-mounted ARS models be installed without a duct cover--and in that case, how long actually is the duct where the filtration takes place? Thanks for your answer in advance!

Hello Houzz Community! I found this thread when Googling a similar topic. I'd like to replace my under cabinet hood with a wall mounted hood, and yes I know I have to remove the cabinet above the current hood which I'm fine with (see photo). My existing under cabinet hood vents out the wall to the side of my house - see photo, and note the vent is not blocked by those shrubs, there is space around it, you just can't tell from the angle of the photo :-) So my question is....can a wall mounted hood be installed to vent out the existing vent in the wall, or does a vent need to be created in the ceiling? Also, what type of professional can help answer any related questions I have about this? Would I ask the wall mounted vent manufacturer? Or a handyman? Thank you in advance for any guidance! I am a newbie homeowner and am learning as I go, so truly appreciate you taking the time to share your knowledge with me!

54-inches (4.5 ft) x 2 ft = 9 sq. ft. Desired volumetric flow rate to achieve 90 ft/min across the hood aperture is 90 x 9 = 810 CFM. Blower rating needed to pull 810 CFM with decent MUA will be around 1200 CFM, as you noted. Fantech provides 'fan-curve' data in the form of tables, and also plots. A 1200 CFM unit (at zero static pressure) will show a value near 810 CFM at some pressure drop (about 1.2 inches, w.c., for the FKD10XL). Excluding MUA, most pressure drop will be from the hood baffles, unless one has several tens of feet of duct. It would be useful for you to obtain pressure loss vs. flow rate data from Bluestar. Fantech in-line blowers are, I think, axial blowers (like a turbo jet pressure section) rather than a flat plate with radial fins (like turbo chargers use). Broan blowers, including inline, appear to all be the plate type. There is nothing wrong with these, but they may have a different characteristic fan curve shape than Fantech's blowers. I've never plotted both together. (It is important for residential blowers operated at uncontrolled pressure losses and any speed from low to high that they have monotonic fan curves. Else they might 'hunt' at some setting. That would be annoying.) Plate type blowers are least conspicuous built into a roof cap. Commercial up-blast blowers use induction motors often tied to the fan assembly via a belt and sheaves. These can be tailored to provide the desired CFM at lower fan speeds, thereby reducing noise. They are, however, significantly more conspicuous on the roof. The primary advantage to using a hood manufacturer's specified blower is that it will directly adapt to whatever fan speed controls are built into the hood. Other blowers may require some type of adapter or control replacement. So a Blue Star hood's control nature might have to be determined. My Wolf hood adapts to my Wolf blower, made by Broan/NuTone, and likely would work with any other single wire pair induction motor blower up to some motor power limit. The Fantech FKD10XL data sheet show curves for a 5-step transformer control, and for no control. One would have to check with them for compatibility with whatever the Bluestar hood uses, such as phase control. If you use an in-line blower, you also have to find a suitable roof or wall cap. Fantech many sell these. You should have a damper at the hood and also at the roof cap. You need to plan out the entire hood duct path. Is there room for a silencer? Can the duct path rise over its entire length (desirable)? What elbows are needed? Fantech makes some duct couplings that may prove useful. Hanger strap material will be needed. Sound dampening material may or may not be needed depending on blower assembly vibration, which is mostly, I expect, due to blower fan assembly balance quality. Best to match MUA actual flow rate to hood actual flow rate (ex: 810 CFM). This avoids all (well most) pressure drop in the house, conferring safety with combustion appliances and keeping the wall dust in the walls. If active MUA is needed to do this (depends on combustion appliances and their MUA, if any) then a blower that can provide the required CFM at the MUA path pressure loss (usually any air filters, but could include the heating scheme if hydronic). As usual, the duct diameter in the hood exhaust should support a full speed flow rate of 1000 to 2000 ft/min. The otherwise clean MUA path is not grease deposition constrained, but larger will reduce pressure loss if there is room -- useful particularly with passive MUA. I'll skip MUA control in this message, but it needs to be addressed. Commercial rigs usually run at constant speed (exhaust and MUA), so tuning is easy. Residential variable flow rate, along with perhaps a need to deal with other exhaust fans and fireplaces, imposes more difficult conditions for blower control. You might need a Fantech MUA setup, or their 10V control type blowers run by a controller trying to keep house pressure relative to outside within some bound.

Hi there! While it isn't the most common, there have been times we have made a very long/large range hood and only need a certain size insert (for example 10' wide hood, only needing a 48" liner), so most often what we would do is install a stainless steel panel to allow everything to look smooth and coherent with the liner. Some people opt to add lighting to the "dead" panel space, and I would definitely recommend making sure you get the proper CFM for your space, but yes you can have an insert smaller than the range hood. Hope this helps!