Abstract：This paper analyzed and repaired a case of Siemens servo series ventilator ventilation failure and a case Maquet servo
series ventilator oxygen concentration low fault to provide experience for breathing machine maintenance. For the ventilation failure
with serious imbalance between the intake and the exhalation of tidal volume, it was found that the air leakage was caused by the
break of the spring pressure plate of the air module nozzle through the progressive investigation, and the reasons were analyzed and
the suggestions were given. The low oxygen concentration fault was found to be caused by insufficient oxygen supply concentration
in the center of the oxygen generator through investigation. The problem was solved preliminarily by coordinating relevant
departments to increase production, and the subsequent problems and related thinking were analyzed. This paper summarizes the
maintenance strategy and puts forward some constructive suggestions through this kind of fault phenomenon.