30 May 2005

DEVELOPMENT OF AN AUTONOMOUS PERFORMANCE-TESTING SYSTEM OF WATER-SOURCE HEAT PUMPS AND ACTUAL PERFORMANCES OF JAPANESE SMALL WATER-SOURCE HEAT PUMP UNITS


Big chillers and large capacity heating units are generally required for performance tests of a water
source heat pump. However, such investments are hard for small factories and an on-site performance
test is needed in some cases. On the other side, there are some requests that an actual operation as the
demonstration of a water source heat pump in exhibitions and trade shows.
The authors developed an autonomous performance testing system of water source heat pumps
which can also be applied to the ground heat source. Basically this testing system requires electric
power only for compressor of heat pump and for circulating pumps. Heat sources and heat sinks are not
needed. A plate-type heat exchanger between the primary side and the secondary side of a heat pump
unit and a fan coil unit for heat release of waste heat enable this concept. Also, this testing system is
very compact and transportable. This paper describes an outline of a developed autonomous
performance testing system for water source heat pumps.
Recently in Japan, a few manufacturing companies have developed high performance small GSHP
units for residential use with a variable speed compressor. In addition to mentioned above, actual
performances of these novel small water source heat pump units made in Japan are also presented in this
paper under various temperature conditions measured by this testing system.