Range Hood FAQ

Your hood is installed directly above hot cooking equipment, and many chemicals found in cleaning agents react with heat to loosen paint. So, stainless steel hoods should be washed regularly with warm water and mild soap or dish detergent. Clean in the direction of the polish lines, rinse well with clean water and wipe dry immediately. To bring out its bright finish, consider using light oil designed for furniture polishing. Be cautious about using “New and Improved” cleaning agents.

Depending on how often you use your range hood, its aluminum mesh grease filters should be washed in your dishwasher once a month, more often if your cooking style includes frying foods or wok cooking. The non-duct carbon filters cannot be cleaned, but replaced. Baffle filters used in professional style range hoods, are designed to operate longer in high-grease environment without a drop in performance. Generally, these need to be cleaned with soap and water whenever you can see the grease and grime.

It depends on the frequency and type of cooking that is performed. Normally, every 3 to 6 months is recommended for replacing the charcoal filters. Some are actually designed with a color indicator that will signal it’s time to replace the filter.

Yes. A number of manufacturers offer under-cabinet range hoods, such as Kobe, Zephyr, Windster, and Broan.

Range hoods really should be ducted to the outside of the home. While duct-free filters trap some of the grease and odors from normal cooking, all of that humidity, smoke and heat will eventually re-circulate back into the home. If your duct-free filters are not replaced regularly, eventually the grease and odor-catching effect will no longer protect your home from impurities. That’s why we recommend ducted range hoods. High BTU gas cooking equipment should always be ducted to the outside of the home. If this isn’t possible, high-performance convertible hoods and filters are available.

Range hoods must be vented using metal duct. If there’s a choice between flexible metal and smooth metal, we recommend the smooth, since the many ridges in flexible metal duct can create turbulence and diminish airflow. Of course, NEVER use 4” dryer duct or any plastic duct on a range hood installation. Additionally, the minimum size duct allowed on most range hoods is 3 ¼” x 10”, equivalent to a 6” circumference. More powerful hoods require even larger duct sizes, up to a 10” circumference. When remodeling and changing hood and cooking equipment types, do not reduce the ductwork size to less than the size specified for the range hood, since doing so restricts the performance of the range hood ventilator.

CFM stands for Cubic Feet Per Minute of exhausting air flow. The higher the number, the more air that’s exhausted. A sone is an internationally recognized unit of loudness. One sone is equivalent to a quiet refrigerator in a quiet kitchen. Typically, the sone level is measured at maximum CFM, but some are also being tested at normal CFM (speed) settings to provide consumers with typical sound level information.

For high output gas ranges or cook tops, the minimum rate of 1 CFM of ventilation per 100 BTU is recommended, with slightly less for conventional electric and gas ranges or cook tops

There is no recognized national standard for the measurement of CFM or sones on this type of hood since the air is simply re-circulated.

Several ways, depending on the model. Your standard 3 ¼” x 10” duct could vent from the top vertically or horizontally through the back, and the 7” round duct vents through the top. Some hoods are single-use ducted and some are convertible, meaning that the hood should be installed using more than one duct method or direction.

The term “convertible” means a hood can be installed in different ducting modes. Typically a convertible hood can accommodate 7” round ducted, 3 ¼” x 10” vertical or horizontal ducted, and non-ducted applications available at installation. Additionally, when talking about convertible hoods, some manufacturers refer to their multiple ducting options. It’s also common to hear convertible in reference to a hood being convertible between wall-mounted or under cabinet. These hoods, of course, come like an under cabinet hood, and if you add a duct cover, it’s been converted to a wall-mounted hood.

For optimal performance, keep the duct straight and short, using the shortest route with the fewest turns possible. 45° turns are better than 90° turns. Be sure to use an external roof or wall cap.

You should NEVER exhaust air into spaces within walls, ceilings, attics, crawl spaces or garages. Humidity and grease will collect in the space, and that’s just not safe.

In a word, no. Installing in-line or external fans to boost a hood’s own power unit will not be effective. Most cooking ventilation products are designed with fan switches matched to the original motor amp ratings and not to support any increased amp draw from additional motor installations. Besides, this type of tampering voids any original manufacturer’s warranty.

Reference each hood’s installation specifications for exact measurements, since each manufacturer will vary.

Hoods that mount to the wall typically need something to attach to. Whether it’s a cabinet or a type of “cubby,” you’ll need to secure the range hood to something.

Yes. We offer a number of extension kits from manufacturers like Zephyr, Broan, Cavaliere-Euro, Windster, and Kobe. Just search for “hood extension.” If this doesn’t work for you, most metal fabricators should be able to custom make one for you, usually at a pretty reasonable price.

Not recommended, since altering the product voids manufacturer’s warranty. We do offer several hoods with remote controls.

Fujioh and Zephyr both offer custom hood liners. Alternatively, you can find a metal fabricator in your area to design a liner for your hood, especially if local building codes require one.

It depends on the manufacturer.

There is no way to use downdrafts with stoves or built-in ovens. The units must only be installed with drop-in cooking equipment.

Many manufacturers offer inserts for custom hoods. Be sure to choose the hood that best fits your hood’s dimensions, your CFM, sone, finish and price requirements. Build.com offers custom range hood inserts from Fujioh, Broan, Zephyr, Kobe, and Vent-A-Hood.

The width is the actual outside measurement of the hood, and nominal width is the space you have available for the hood. For example, if you have a 30” space, you’d look for a range hood with a 30” nominal width.