In this study, a concept of using phase change material (PCM) for improving cooling
efficiency of an air-conditioner had been presented under Thai climate. Paraffin waxes
melting point at around 20 1C was selected to evaluate the thermal performance by
reducing the air temperature entering the evaporating coil. The model of PCM celluloid
balls had been performed with the air-conditioner. Moreover, the mathematical model of
the air-conditioner with the PCM storage was developed and verified with the testing
results. From the study results, it could be seen that the simulated data agreed quite well
with the experimental result at the discrepant around 2–4%. Finally, the model was used
to analyze the economic result which was found that the electrical consumption of the
modified air-conditioner could be decreased 3.09 kW h/d. The electrical power consump-
tion of the modified unit was 36.27 kW h/d at the operating time 15 h/d compared with
39.36 kW h/d of the normal unit at the operating time 12 h/d. The saving cost of the PCM
bed could be 9.10% or 170.03 USD and the payback period was 4.15 y.
& 2014 The Authors. Published by Elsevier Ltd. This is an open access article under the CC