We developed air conditioning equipment inspection robot with vision sensor. Because the resent high-rise building has many air diffusers for air conditioning, inspections of these diffusers are very hard work for human labors. Then our robot is expected to do this hard work to substitute for human labors. This robot has a CCD camera with pantilt table and wheels controlled by computer. So the robot can find out air diffusers by CCD camera and move to the air diffuser automatically. After the robot reaches to the diffuser, the robot lifts up air volume sensor system to the ceiling in order to measure the air temperature and the air volume of the diffuser. In this paper, we state on our proposed recognition method of diffusers, robot navigation based on ceiling landmarks, and the sensor system which measures air volume flowed out from the diffusers. In experiments, we compare the data measured by human labors with the data by our developed robot, and experimental results prove that our robot is enough to substitute for human labors.