Effects of Recirculation and Ventilating Airs on Performance of Air-Conditioning Systems

Abstract

The effects of recirculation and ventilating airs cannot be over emphasized in air-conditioning(AC) systems. These two important factors in AC systems affect COP, required air change and power required to run the system. Most of the available works are based mostly on the identified space and not the actual effects of these two factors. This work considered the effects of these two factors on the performance of a single duct variable volume (SDVV) air-conditioning system. During the experimentation both ventilating and recirculation airs were varied between 0 kg to 1.25 kg. Also the duties of both cooler and heater coils were adjusted to meet the room supply condition while keeping the room ratio line constant at 0.85 gradient. It was discovered that for minimum running cost and the air change required for human comfort to be maintained both ventilating and recirculation airs should be kept at 50% each.