Published Paper Details:

HFC-161 (Fluroethane) is being considered as an alternative to HCFC-22 in air conditioners. It has zero ODP and ultra-low GWP. The thermophysical properties of HFC-161 are very close to HCFC-22 except flammability. The lower flammability limit of HFC-161 is 3.8% by volume in air, which is almost double of HC-290. It is reported that it has good compatibility with mineral oil. HFC-161 has not yet been classified by ASHRAE Standard 34 for safety. This paper discusses the simulated results on the suitability of HFC-161 as an alternative to HCFC-22 for room air conditioning applications. The simulation has been done using computer simulation tool for drop-in conditions as well as for some design variations including compressor capacity and condenser area. The results show that the cooling capacities are comparable with HCFC-22 and HC-290. COP is higher than both HCFC-22 and HC-290. The discharge temperatures are lower than HCFC-22 but higher than HC-290. EN 378 specifies the allowable charge in a closed space to avoid any risk due to flammability. While the limit is about 8g/m3 for HC-290, it is about 15 g/m3 for HFC-161. For an air conditioner with a nominal cooling capacity of 5.2 kW, one has to take special efforts to meet this limit for HC-290. However, it may be possible for HFC-161 to meet EN 378 without many changes in the heat exchanger configurations. In this paper, the simulated performance of split air conditioners (SAC) using HFC-32 with nominal cooling capacity of 5.1 kW was studied. The simulation has been carried out for SAC using test conditions prescribed in Indian Standards IS 1391 (1992) Part I. The simulation has been carried out for variation in compressor capacity, capillary, and exchanger tubing. The results showed that COP improvement for HFC-32 air conditioner is about 8% when 5 mm tube OD was used for condenser. There is marginal improvement in COP when capaillary optimization was performed.