The paper presents comparison in flow characteristics for CFC-12 and HFC-134a in capillary tube. The results revealed that even with minor differences in refrigerant properties between CFC-12 and HFC-134a, the differences in flow characteristics may be significant. Theoretical results predicted that 15% difference or more in critical tube length may be expected.
Wong, T. N., & Ooi, K. T. (1996). Evaluation of capillary tube performance for CFC-12 and HFC-134a. International Communications in Heat and Mass Transfer, 23(7), 993–1001. https://doi.org/10.1016/0735-1933(96)00081-4