Application Engineering Application Engineering B L LL E L T EI BU U N T I N AE December 1994 AE17-1284 R1 Reformatted November 2010 Switching Refrigerants in Field Installations As a result of price increases and possible shortages of the commonly used refrigerants caused by the CFC issue, substantial interest has developed in switching refrigerants in existing systems (such as switching CFC-12 systems to CFC-502 or HCFC-22 and switching CFC-502 systems to HCFC-22). In most cases, such a switch is not economically justified as Emerson Climate Technologies believes most existing systems will be able to be maintained for their useful lives by recycling existing refrigerants and repairing leaks. components. Furthermore, the capacity of the system may change substantially and the reliability of many of the components may be severely compromised. Because of these problems Emerson does not advocate switching refrigerants in existing systems. Before such a change would be undertaken, a comparison of the potential costs and benefits of switching refrigerants should be made and specific approval and recommendations from the original equipment manufacturer should be obtained. Emerson strongly recommends against switching refrigerants without doing an extensive engineering evaluation of the system. Refrigeration systems are highly engineered for a specific application with a specific refrigerant. As a result, switching refrigerants in an existing system will strongly affect the operation of major system components such as the compressor, operating controls, expansion valves, pressure actuated valves, condenser fan controls, and safety controls. In addition switching refrigerants may require major system piping changes due to differences in gas velocity and oil return characteristics. Switching refrigerants could also reduce system efficiency and cause new leaks in the system because of higher operating pressures. These higher pressures could create a potential safety hazard in the case of structurally weak © 2010 Emerson Climate Technologies Printed in the U.S.A. As alternative refrigerants to CFC’s become available in the marketplace, Emerson will publish guidelines for retrofitting to existing compressors as appropriate. These are available for the following: R-12 to R-134a R-502 to R-404A/R-507 R-12 to R-401A R-12 to R-401B R-502 to R-402A It is expected that OEM system manufacturers will provide similar information for their equipment. 1 Application Engineering B U L L E T I N ADDENDUM The contents of this publication are presented for informational purposes only and are not to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. Emerson Climate Technologies, Inc. and/or its affiliates (collectively "Emerson"), as applicable, reserve the right to modify the design or specifications of such products at any time without notice. Emerson does not assume responsibility for the selection, use or maintenance of any product. Responsibility for proper selection, use and maintenance of any Emerson product remains solely with the purchaser or end user. CAUTION POE must be handled carefully and the proper protective equipment (gloves, eye protection, etc.) must be used when handling POE lubricant. POE must not come into contact with any surface or material that might be harmed by POE, including without limitation, certain polymers (e.g. PVC/CPVC and polycarbonate). © 2012 Emerson Climate Technologies, Inc. Printed in the U.S.A.
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