Details of a heat pump assisted solar water heating system, is briefly described. Refrigerants compromising of Fluorocarbons and Chlorofluorocarbons have been generally used as the working fluid. But due to its ozone depletion effect and high Global warming potential, they have been replaced by synthetic refrigerants such as R22, R134 etc. The heat pump utilizing such refrigerants has shown to ...

Recently, R32 refrigerant, which has low global warming potential (GWP), attracts much attention as an alternative one instead of R410A and has started to be used in practical systems of room air conditioners (RAC), but compared with natural refrigerants, its GWP of 675 is still high and it is required to use refrigerants with much lower GWP. In addition, although R134a (GWP=1300) is widely use...

In many cases, polyol ester (POE) and polyalkylene glycol (PAG) lubricants used with HFC refrigerants, may cause long-term reliability and stability problems. Mineral oil lubricants are much more stable in the long run and do not suffer from stability problems nearly as much as POE and PAG lubricants. HFC based refrigerants and blends are, in general, nonmiscible in mineral oils, and will not r...

Growing concerns about the global warming impact of refrigerants used in HVAC&R equipment are driving development and evaluation of alternative refrigerants with lower global warming potentials (GWPs). The Air Conditioning, Heating, and Refrigeration Institute (AHRI) recently coordinated the Low-GWP Alternative Refrigerant Evaluation Program (AREP) in which commercial, university, and governmen...

The paper presents a study of refrigerants and some issues relating to their environmental impacts in HVAC&R equipment. They are treated aspects of the environmental pollution through the working fluids of the air-conditioning, refrigeration and heat pump systems, and a new strategy in using refrigerants in accordance with the international legislation is described. Additionally, this study pre...

Madeleine R. Johnson AGMC/MAEL 813 Irving Wick Drive West Newark AFB, Ohio 43057-5149 This paper describes the initial results of a refrigerant retrofit project at the Aerospace Guidance and Metrology Center (AGMC) at Newark Air Force Base, Ohio. The objective is to convert selected types of test equipment to properly operate on hydrofluorocarbon (HFC) alternative refrigerants, having no ozone ...

The use of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) has been widely restricted. They have been replaced with hydrofluorocarbons (HFCs) in order to protect the ozone layer. However, the leakage of refrigerant into the air from active or end-of-life air conditioners is a serious environmental issue owing to the high global warming potential (GWP) of HFCs. Therefore, replaci...

The Air-Conditioning, Heating, and Refrigeration Institute (AHRI) recently completed the first phase of its low global warming potential alternative refrigerants evaluation program (Low-GWP AREP). This industry-wide cooperative research program identified and evaluated promising alternative refrigerants’ performance over the past two years. Thirty-eight low-GWP refrigerants were tested during t...

the present study investigates the performance and relative accuracy of four lattice-hole theory based equations of state in modeling and correlating the liquid density of pure refrigerants. following the gathering of a database of 5740 experimental liquid density datapoints of 36 pure refrigerants belonging to five different categories including cfcs, hcfcs, pfcs, hfcs and hfes, ranging from 6...