The application of exhaust fans in summer can be said to be the peak of the year. Frequent use will inevitably cause failures. Before the hot weather comes, we need to check the fans and troubleshoot them. The following is an analysis of the main failures of several common negative pressure fans（exhaust fans）. as follows:
1. Circuit problems: including power failure, poor or damaged wire contact, circuit board failure, motor burnt out or lack of phase, etc. This may prevent the exhasut fan from starting or working properly.
2. Wear and aging: Long-term use or improper maintenance of the fan may cause the impeller to wear or age, thereby reducing the efficiency and performance of the exhaust fan.
3. Pollution and blockage: Dust, grease and other impurities may accumulate on the fan impeller or louver, causing the fan speed to decrease or the noise to increase.
4. Bearing failure: Long-term use of the bearing or lack of lubrication may cause fan bearing failure, manifested as noise, vibration or unstable speed.
5. Belt wear: Severe belt wear will cause the fan speed to decrease and the air volume to be insufficient. It needs to be tightened and replaced regularly.
For the above problems, exhaust fan failures can be prevented and solved by regular maintenance and cleaning of the fan, checking circuit connections, and replacing worn parts. In addition, regular inspection and maintenance are also important means to maintain the stable operation of exhaust fans and extend their service life.
