abstract |
The invention provides a heat transfer composition comprising (i) a first component selected from trans-1,3,3,3-tetrafluoropropene (R-1234ze(E)), cis-1,3,3,3-tetrafluoropropene (R-1234ze(Z)) and mixtures thereof; (ii) carbon dioxide (R-744); and (iii) a third component selected from propylene (R-1270), propane (R-290), n-butane (R-600), isobutane (R-600a), and mixtures thereof. |