Performance of a residential air conditioning unit under constant outdoor air temperature and varied relative humidity

An experiment on the effect of the relative humidity variations of outdoor air on the performance of an air conditioning system under constant dry-bulb temperature has been performed. In this experiment, the outdoor air temperature was maintained at 35°C while the relative humidity was varied from 40% to 70%. As a result, the operating conditions were slightly changed. In general, the suction temperature decreases with the increase of relative humidity. On the other hand, the condensing temperature slightly increases with the increase of relative humidity. Other findings for the experiment are almost constant of cooling capacity, with a variation of only 1.2%. An important evidence is that the condenser capacity increases by 15.2% for the relative humidity variation from 40% to 70%.