An air flow probe is a device used to measure the air flow rate in a system. It is typically used in HVAC systems, air conditioning systems, and ventilation systems to measure the amount of air that is being circulated. The air flow probe is typically placed in the ductwork of the system, and it measures the velocity of the air passing through the duct. The velocity of the air is then used to calculate the air flow rate. The air flow rate is important for determining the efficiency of the system, as well as for determining the amount of air that needs to be circulated to ensure the desired temperature and humidity levels. The air flow probe is a critical component of any HVAC system, and it is important to ensure that it is functioning properly in order to ensure the system is running efficiently.