Abstract
While the concerns about global environmental issues are on the rise, natural refrigerants and heat pump systems of high efficiency attract attention as a measure to combat ozone layer depletion and global warming. This work presents the development work of a heat pump chiller for air-conditioning, using the natural refrigerant ammonia as the refrigerant. Using a newly developed evaporative condenser and a high efficient compressor, we attained a unit COP of 5.1/4.9 (at 50/60Hz) in the cooling operations. A sealing damper was used in order to raise the safety level of the chiller in the event of ammonia leakage. In addition, the installation space was drastically reduced by building an ammonia removal system in a unit. Japan, as an earthquake-prone country has imposed strict regulations on the use of ammonia refrigerant. With the construction of the present work, we have been able to produce an ammonia removal system, which is easy to use but less likely to cause concerns on ammonia leakage.
