An air flow sensor for HVACHVAC (Heating, Ventilation, and Air Conditioning) is a device that measures the rate of air flow in a duct system. It is typically used to measure the amount of air entering a room or space, or to measure the amount of air passing through a particular component in the system. Air flow sensors are typically used to ensure that the air flow is balanced and that the air flow is within the desired range. They can also be used to detect blockages in the system, such as dust or dirt, and to monitor the performance of the system. Air flow sensors are typically installed in the ductwork of the HVAC system, and can be either mechanical or electronic. Mechanical air flow sensors measure the pressure of the air passing through the duct, while electronic air flow sensors measure the speed of the air. Air flow sensors are an important part of the HVAC system, as they help to ensure that the system is running efficiently and that the air quality is optimal.