Features Designed To Provide The Best Technology To Equalize Pressure Between Indoors And Outdoors, While Providing Effective Ventilation For A Cleaner, Healthier Home. Eliminate Gases, Smoke Or Particulates Generated From Naturally Vented Combustion Devices Like A Fireplace Or Water Heater. Only Best Offers Such A Complete And Simple Solution For Automatic And Controlled Fresh Air Into The Home Every Time You Turn On The Range Hood! This Is An Interlocked, Synchronized System That Installs Easily And Requires Only Low Voltage Wiring To The Sensor. Perfect For New Construction Or Retrofit Into An Existing Home. (Ul)(Li)Best Interlocked Make-Up Air Dampers Provide Outside Air When Required To Keep The Air In The Home Fresher By Allowing The Range Hood To Operate At Optimum Levels(/Li)(Li)Universal Design Works With Any Best Range Hood To Balance Indoor Air Pressure By Providing Interlocked Make-Up Air Without Requiring A Direct Wire Connection Between The Range Hood And The Damper. Instead A Sensor Is Attached To The Exhaust Duct To Detect If The Range Hood Is Operating(/Li)(Li)Slave Dampers (Md6S Or Md8S) Are Interlocked To The Main Automatic Or Universal Make-Up Air Damper And Open In Unison For Synchronized Operation. They Close, Along With The Main Damper, As Soon As The Range Hood Is Powered Off. Slave Dampers Can Be "Ganged" Together To Provide A Cost Effective Means To Provide For Higher Volumes Of Make-Up Air(/Li)(Li)Interlocked Make-Up Air Damper Systems Meet Irc Code Requirements For Make-Up Air With Range Hoods Over 400 Cfm(/Li)(Li)Interlocked Make-Up Air Systems Avoid Wasted Energy Associated With Barometric Solutions And Do Not Let Unwanted Air Into The Home During Heating Or Cooling Activities So Air Pressure Is Equalized For A Well-Balanced Environment(/Li)(Li)Fresh Air Wall Caps Are Required For Use With Make-Up Air Dampers(/Li)(/Ul)