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A Water-to-Water Heat Pump Using Hydrocarbon and Hydrofluorocarbon Zeotropic Mixtures With and Without an Internal Heat Exchanger
Published
Author(s)
William V. Payne, Piotr A. Domanski, E A. Silk
Abstract
This investigation overviews the comprehensive results of the experimental study pertaining to flammable refrigerant alternatives in water-to-water heat pumps for building and home applications. In contrast to the comprehensive fluid survey of the initial study (NISTIR 6330, 1999), the present study emphasizes the performance of R32/290, R22, R290, and R22-REF (direct expansion case) in the cooling and heating modes. The vapor compression cycle used had an internal heat exchanger added. Fluid performance as a function of thermophysical properties and heat transfer characterisitics are addressed for each cycle configuration.The system charged with R32/290 had the closest performance to the R22 direct expansion system in the cooling mode. Furthermore, the internal heat exchange system performance exceeded that of the basic vapor compression cycle configuration. In the heating mode, R290 in the basic configuration had the closest approximation to the R22 direct expansion performance. The application of the internal heat exchanger degraded R290's performance.
Payne, W.
, Domanski, P.
and Silk, E.
(2000),
A Water-to-Water Heat Pump Using Hydrocarbon and Hydrofluorocarbon Zeotropic Mixtures With and Without an Internal Heat Exchanger, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.IR.6449, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=860803
(Accessed October 14, 2025)