Questions and Answers for Arietta Universal No Return Valve for 6 in. Round Ducting

A:  Hello 6" round is commonly used to support range hoods with 300-600 cfm. CFM = cubic feet per minute and relates to how much air the blower can move. The min air flow is generally not the concern. It's the max airflow. If you use too small duct it can create back pressure, stress the blower, cause over heating and failure. In other words, if an installer used 6" duct to support one of our powerful 1200 hoods, it would void the warranty. The more important issue might be the path of the ducting. With each 90 degree turn, you lose about 10' of run. Example, a 600 cfm hood can generally push air about 80 feet. However, for every 90 degree turn, you deduct 10' off the max run distance. Hope this helps. Regards,

A:  No. They are very different and have completely different functions. Recirculation kits are used as an alternative to installing metal ducting and ducting the air to the exterior of your home. Essentially the range hood draws in dirty air, the air is cleaned by grease and carbon filters, then re-introduced back into kitchen as clean air. A Recirculation kit usually contains a Deflector and Carbon Filters. A Universal No Return Valve is used when you are ducting out. It prevents air from the outside from entering the home. With a No Return Valve, air can only flow from the kitchen to the outside. This prevents cold drafts of air entering the home in winter and hot drafts in the summer. Regards,