STUDY ON THERMAL PERFORMANCE OF R-32 AIR-CONDITIONER

Abstract

In this study, cooling performances of an air-conditioner with R-32 refrigerant compared with R-410a under controlled conditions similar to Thai climate were evaluated. Two air-conditioners with R-32 and R-410a refrigerants were installed in a well-insulated testing room of 2.45 m x 2.60 m x 6 m. The testing room was separated into two sections for each evaporating unit and condensing unit. The thermal performances were considered when the distances between each evaporating unit and condensing unit were at 10 m and 15 m. The air temperatures entering to the condensing coils and the evaporating coils were controlled by electrical heaters and in the vicinity of the evaporating coils there was a water spray to control the humidity. It could be seen that the lapse time to achieve steady state condition of R-32 unit was around 15 minute which was 3 minute quicker than that of R-410a unit. For 10 m of the piping tube, the EERSys of R-32 unit was slightly higher than that of R-410a unit for all testing conditions. The values were 3.401 kWth/kWe and 3.395 kWth/kWe for R-32 and R-410a units at the evaporating temperature and the condensing temperature around 25oC and 40oC, respectively. For 15 m of the piping tube, it could be found that the EERSys of R-32 unit was also slightly higher than that of R-410a unit for all testing conditions. It could be concluded that R-32 air-conditioner gave better cooling performance compared with R-410a unit. It was also noted that R-32 was friendly more to the environment thus this one was appropriate to replace R-410a.