In air-conditioning applications, the temperature of air is measured by inserting a probe into the flow stream. Thus, the probe actually measures the stagnation temperature. Does this cause any significant error?
In air conditioning applications, the temperature measured using a probe gives stagnation temperature which is equal to the static temperature because the velocity of the air is very low. The air molecules have lower kinetic energy because the molecules of air in the air conditioning applications possess very low velocity. As a result, the temperature change is negligible and the static value of temperature to its stagnation value. The error can be significant only if the air stream in supersonic.
Therefore, there is no significant error when temperature is measured with a probe in air conditioning applications.