The thesis deals with the theoretical foundations related to moist air and the measurement process. The experimental part of the measurement is carried out in an air conditioning chamber and the analysis and comparison of the obtained measurement results is carried out. In the theory of moist air, the basic state quantities and basic processes with moist air are described, as well as the principles of operation of measuring transducers. The experimental part of measuring humid air is reduced to measuring the temperature of a wet and dry thermometer and determining the state using known temperatures. In the first experiment, during one of the measurements, large oscillations between the set and realized parameters were observed, and an assumption was made as to why this occurs. The second experiment was a test of the stability of the air conditioning chamber, for several different temperatures. By processing the results of the second experiment and comparing them with the results from the first experiment, the suspicion was confirmed that there was no accidental error, but that the air conditioner has a very difficult time following the operating mode at low temperatures, while at higher temperatures it has a better following of the set values. However, for some processes, the form of the response is not important, but the mean value, therefore a comparison of the results for the mean effective value of relative humidity was made. If the operation of the air conditioning chamber is observed in real time, then it can be said that it hardly follows regimes of lower temperatures, and better at higher temperatures. But if the mean value of relative humidity is monitored, then the response is within acceptable limits for both regimes. The only problem arises when low and high relative humidity needs to be achieved, because then excessive drying or humidification occurs, then due to device limitations, the disturbance cannot be quickly compensated for, so it takes a long time to return to normal working condition.