| abstract |
This working medium that is for heat cycles and that uses (Z)-1-chloro-2,3,3,3-tetrafluoropropene (HCFO-1224yd(Z)) which has less impact on the ozone layer, has less impact on global warming, and has superior cycle performance, is provided so as to have sufficiently ensured stability and to have high productivity. The working medium for heat cycles which contains HCFO-1224yd(Z) and impurities, is characterized in that the impurities include specific trace components, and the total content of the trace components is less than 1.5 mass% with respect to the entire amount of the working medium. |