Measuring air flow in an HVAC duct can be a tricky business ... The principle behind the sensor [ItMightBeWorse] is working on is nothing new. He discovered a paper from 2015 that describes ...

With disposable towels, wipe away any loose dirt or dust from the MAF sensor, as well as all air ducts. Take your time ...

His experiments in air duct flow measurements, which previously delved into ultrasonic flow measurement, led him to try mechanical means. That calls for some kind of turbine producing a signal ...