Abstract: The air extraction tubes of highpressure condenser and lowpressure condenser in a unit were arranged in series mode, and this caused the extracted air of highpressure condenser to push aside the extracted air of lowpressure condenser. The air extraction of lowpressure condenser was not reached to the designed requirement; the vacuity of the lowpressure condenser was lower, and the difference between highpressure condenser and lowpressure condenser was also lower. Then the system economical efficiency was decreased. The air extraction system of twopressure condenser had been reformed by adopting some relevant measures, and obvious economical benefit was obtained. 

Key words: two-pressure condenser, air extraction system, pressure difference of terminals, vacuum, reformation scheme