To ensure good indoor air quality and ideal air distribution within a residential ventilation system, it is important that the volume flows at air vents are set correctly. The growing awareness of good indoor air quality is manifested, for example, in the IDPH Guidelines for Indoor Air Quality. From time to time, it is therefore advisable to check the air flows by means of measurement. There are various methods that can be used here, such as funnel measurement with a large vane manometer or hot wire anemometer.