Study of a Water-to-Water Heat Pump Using Hydrocarbon and Hydrofluorocarbon Zeotropic Mixtures.
Study of a Water-to-Water Heat Pump Using Hydrocarbon
and Hydrofluorocarbon Zeotropic Mixtures.
Payne, W. V.; Domanski, P. A.; Muller, J.
NISTIR 6330; 39 p. May 1999.
Available from: National Technical Information Service
(NTIS), Technology Administration, U.S. Department of
Commerce, Springfield, VA 22161.
1-800-553-6847 or 703-605-6000;
Order number: PB99-152373
heat pumps; water; hydrocarbons; zeotropic mixtures
This investigation compared the performance of R22 to
the performance of propane (R290) and zeotropic mixtures
of HFC's and hydrocarbons in a water-to-water heat pump.
Baseline testing began with R22 and proceeded to R290,
R32/290, R32/152a, and R290/600a. The use of brazed
plate heat exchangers arranged in counterflow for both
heating and cooling allowed glide matching using the
zeotropic refrigerant mixtures. The performance of the
system was characterized by air-side capacity, air-side
COP, compressor RPM, and refrigerant conditions. Testing
showed that the R32/290 (5O/50 by mass) mixture produced
the highest cooling COP for a given capacity averaging
17% higher than R22 at standard conditions. When
compared to the simulated direct expansion R22 system,
the R32/290 cooling COP averaged 11% lower. Heating
tests showed that propane (R290) COP averaged 3% lower
than R22 in the direct expansion simulation and 5%
higher than R22 in the water-to-water tests. R32/290
heating COP averaged 10% lower than R22 in the simulated
direct expansion configuration.