Abstract
We have been developing a heat carrying system using CO_2 as a secondary refrigerant. The main target of this system is large-size refrigerator for commercial use like show-case for supermarkets. This system is composed two cycles, one is refrigeration cycle using R22, R134a or HC, the other is heat carrying cycle using CO_2. Due to this cycles, the amount of primary refrigerant can be reduced drastically. In this paper, we described basic composition and the specifications of the CO_2 heat carrying system, test results and evaluation of its performance.
