Best recirculating air hood?
millej
17 years ago
Featured Answer
Sort by:Oldest
Comments (20)
millej
17 years agoverysleepy
17 years agoRelated Discussions
Best WT321 hood with automatic make-up air
Comments (10)Generalizing negative pressure development or lack thereof on the basis of the size of the house is too inexact for my taste, given that the risk is combustion product back-flow into the house. One should measure the pressure, or test for back-flow, or both. This requires that the house not be under construction. It is possible with high cfm exhaust fan capability to develop enough negative pressure for back-flow even with an open, but screened window. (Notice the generalization here neglects to mention the nature of screen, the size of the opening, and other factors, thus making it only a warning and not a rule.) I think it sufficiently conservative to plan for MUA and then test to see if it is needed once the construction is settled enough that the house leakage is representative of its finished condition. If the leakage is insufficient, then one has to adapt the MUA to the external conditions. Don't forget that house leakage only occurs when the interior pressure is negative relative to the outside, and balance will occur between leakage in and air flow out. In other words, as the vent fan spins up the house pressure will go negative, the leakage will increase, and the steady-state fan cfm capability will just equal the leakage at that negative pressure. One approach to evaluating the scale of MUA required is to find someone, often associated with energy saving organizations, who has the equipment to measure the pressure differential as a function of the operation of combustion sources and kitchen ventilation. Another is to buy a suitable sensor and do the experiments oneself. In a low dust and pollen area with temperate weather, a big hole with a damper would be sufficient. Otherwise, a filter is needed. The pressure drop across a good furnace dust filter can easily exceed 0.1 inches of water, depending on air flow and filter size. If there is insufficient supplementary leakage to keep the pressure drop low, as is assumed here, the system will need a fan to boost the flow because 0.1 inches of water will cause back-flow of most combustion heat sources. If the environment is cold, then MUA heating is needed. This can be by electric coils, or by a hot-water heating system heat exchanger, or by introduction of outside air into a hot-air furnace system or into an air conditioning system where the cold air ends up being introduced into widely dispersed areas that might have sufficient room heating for the task. The solution will very much depend on the house configuration and its heating system. kas...See MoreBest Recirculating Island Hood?
Comments (1)You might want to look at Prestige. Their conventional hoods are excellent and they do show a no-vent option. Here is a link that might be useful: Prestige No-Duct Hoods...See MoreRecirculating kitchen hood--baffles or mesh filters better? Model reco
Comments (5)I haven't searched for one, but it is possible that Broan/Best has a recirculating system with both grease filtering and charcoal-based odor filtering. To the question: Generally baffle filters are superior in grease extraction efficiency. This is why commercial hoods use baffles. Specifically, the baffles remove the larger end of the particle size spectrum while retaining their performance no matter how much grease is collected. The smaller end of the spectrum is expected to (hoped to) exit the system on the roof. The pressure loss of the baffles remains the same, greasy or not, and this allows the overall air flow to remain constant. However, baffles work by centrifugal extraction due to the air making two reversal in the baffle space. This requires some minimal velocity that likely depends on the details of the baffle design. For modest cooking where low blower speeds are adequate, there is a point where mesh filters -- if kept clean -- may become superior grease collectors. Mesh filters work by impingement. A hybrid baffle system seems to be intended to filter by mesh while providing the appearance of a baffle system. In some commercial applications, the stringent filtering requirements lead to stacked filters, the first usually being baffles, followed by mesh, ball bearing, and other schemes that address different parts of the particle spectrum. UV disassociation of grease and odor molecules is also popular....See MoreChimney is better than under cabinet for recirculating hood-yes or no?
Comments (5)It isn't the CFM at the baffles, as this varies with the baffle area for a given blower. It is the velocity at the hood aperture that becomes a higher velocity at the baffles (inversely proportional to their gap area) that determines entrainment. And your CFM values are blower ratings, not actual flow rates. While baffles perform centrifugal extraction, for which higher velocities are more extractive, a given baffle design will likely have a lower velocity limit for adequate performance. Charcoal filters, on the other hand, might perform best if the flow rate were low per unit area. Charcoal works by adsorption, and I expect gentle contact to be the most effective, but I have never read anything related to that issue. In any case, as I'm sure you would have noticed reading enough hood threads here, for hot oil cooking a hood entry velocity of 90 ft/min is deemed (by me) to be adequate for residential hoods with low reservoir volumes. It may be understood that lesser cooking conditions can be addressed by lower velocities, and boiling eggs by the hood being off. Adequacy really depends on hood reservoir volume, and percentage of the hood entry aperture that the baffle gaps equal. Without computational fluid dynamics analysis of the entire configuration, starting at the pan, or use of a test kitchen, it is difficult to make unqualified pronouncements. Look for a hood that can do 90 CFM per square foot of entry aperture when at full power accounting for the pressure losses vs. the hood blower's fan curve. You probably won't find a recirculating one, or won't find the data. Residential hood manufacturers do not in general (some exceptions such as Wolf) provide blower fan curves, and I do not believe that the ARS even meets the worst case plume velocity suggested actual flow rate. You are in compromise heaven with the most expensive solution, and more affordable units will be even more compromised. Accept your fate, or move. [humor attempt]...See Moreplumorchard
17 years agomillej
17 years agoamysrq
16 years agorgillman
16 years agomad_p67
16 years agoguadalupe
16 years agocuriousnyc
16 years agorgillman
16 years agoverysleepy
16 years agocuriousnyc
16 years agopremier
16 years agopremier
16 years agomillej
16 years agorgillman
16 years agopremier
16 years agojim1963
16 years agopamela928
16 years ago
Related Stories
LIFE6 Ways to Cool Off Without Air Conditioning
These methods can reduce temperatures in the home and save on energy bills
Full StoryKITCHEN DESIGNHow to Choose the Right Hood Fan for Your Kitchen
Keep your kitchen clean and your home's air fresh by understanding all the options for ventilating via a hood fan
Full Story5 Stunning Modern Range Hoods
Today's kitchen range hoods can look like sleek sculptures. Here's what to look for when you go shopping for one
Full StoryMOST POPULAR5 Ways to Hide That Big Air Conditioner in Your Yard
Don’t sweat that boxy A/C unit. Here’s how to place it out of sight and out of mind
Full StoryDECORATING GUIDES12 Ways to Cool Your Home Without Air Conditioning
If your summer energy bill is leaving you hot under the collar, consider these savvy alternate strategies for cooling down
Full StoryKITCHEN APPLIANCESWhat to Consider When Adding a Range Hood
Get to know the types, styles and why you may want to skip a hood altogether
Full StoryKITCHEN DESIGNWhat to Know When Choosing a Range Hood
Find out the types of kitchen range hoods available and the options for customized units
Full StoryKITCHEN APPLIANCESThe Many Ways to Get Creative With Kitchen Hoods
Distinctive hood designs — in reclaimed barn wood, zinc, copper and more — are transforming the look of kitchens
Full StoryKITCHEN DESIGNWood Range Hoods Naturally Fit Kitchen Style
Bring warmth and beauty into the heart of your home with a range hood crafted from nature's bounty
Full StoryKITCHEN DESIGNThe Cooking Hearth Never Looked So Good
Today's Range Hoods Have High Style to Match Their Function
Full Story
curiousnyc