Also, it is found and analysed that there exists inlet pressure fluctuation of coiled capillary tubes when the degree of subcooling is changed from one to another.

In this paper, the influences of these factors on the optimum vacuum are analyzed firstly, and the calculation method of condensate subcooling degree and the dissolved oxygen in condensate are given.

Outlet subcooling degree of reverse flow section should be in conformity with the requirement of HEI Standard.