The objectives of this paper are to study the heat transfer characteristics on enhanced surfaces, to develop experimental correlations of friction factor and Nusselt number, and to provide a guideline for optimum operation conditions at low temperature boiling for practical refrigeration applications. The working fluid (water, EG $30\%$) flows inside the enhanced tube and R134a boils on the outer surface. Two different types of Turbo-B tubes (Tube I and Tube II) are tested in the present study. The results show that Tube I gives a higher heat transfer coefficient with higher friction factor than Tube II. The present study provided experimental correlations for friction factor and heat transfer coefficient with error bands of ${pm}5\%;and;{pm};15\%$, respectively.