Results of a Field Test Using R-407C in Split System Heat Pumps

Abstract

This paper discusses the results of a field test to determine implications of an R-407C replacement of R-22. A change of refrigerants precipitates other changes in materials, component selection, and processing. In addition, thermodynamic properties are different. Consequently, the effects on durability, thermal performance, humidity control, servicing, and manufacturability were questioned. The field test addressed many of these questions. Anticipated changes in manufacturing processes were implemented on the production line. Contractors were educated on the differences in the refrigerant. Data were obtained by refrigerant, lubricant, and component tear down analysis. Experiential information was derived from feed back of contractors and home owners, as well as multiple site visits. Generally, the field test has demonstrated that by following a few basic rules, the industry can anticipate use of R-407C with satisfactory results. However, the surprising appearance of a contaminate precipitant indicates the need for more investigation into long term effects.