Energy Saving for a Split-Type A/C Using together a Condensate Water with Air Ventilation

Chanwit  Wittayavirote; Chanon Bunmephiphit

doi:10.69650/rast.2026.266343

Authors

Chanwit Wittayavirote Rajamangala University of Technology Rattanakosin, Nakhon Pathom 73170, Thailand
Chanon Bunmephiphit Rajamangala University of Technology Rattanakosin, Nakhon Pathom 73170, Thailand

DOI:

https://doi.org/10.69650/rast.2026.266343

Keywords:

Air Conditioning, Condensate Water, Energy Saving, Ventilation Air, Split-Type

Abstract

The study aims to reduce the temperature of the incoming air prior to condenser cooling by mixing and exchanging heat with ventilation air and cool condensate water. The study room was designed 2.4 m×2.9 m×2.2 m and had an installed split-type air conditioner of 12,000 BTU/hr and a fixed-speed compressor, that existing ventilation fan was used with a condensate–air heat exchange panel. The measurement condition included ambient temperature and relative humidity. Electrical consumption was from meter measurement, the study room was fixed 25°C and ambient range 28.1–38.0°C. The experiment details, Case 1, representing the air-conditioning system, and Case 2, the condensate-water and ventilation-air heat exchange system. The results of the study, for Case 1, the average coefficient of performance (COP) of 3.51, energy efficiency average ratio (EER) of 9.31. For Case 2, the average COP and EER increased to 3.69 and 10.27, respectively. The case study compared with the conventional system, the COP increased 5.23% and EER 10.69%. These demonstrate that the integration of condensate water and ventilation air for heat exchange effectively enhances the energy efficiency of the air-conditioning system and contributes to a reduction in energy consumption. The proposed method is therefore considered a practical and energy-efficient solution for improving air-conditioning performance in office buildings.

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