1. Check valve failure

In case of oil fume backflow or odor channeling, check the check valve first, because the check valve is a switch connecting the flue and the range hood, which can ensure that the oil fume can be discharged smoothly without being run in by the oil fume in the flue. If the check valve fails to close or is not installed, it is inevitable that it will be refluxed by oil smoke. It is recommended to check the check valve every once in a while and replace it in time if there is any problem.

second, the doors and windows are sealed

when using the range hood, if the kitchen doors and windows are closed and there is no ventilation to form convection, it will be difficult to discharge the oil fume. At this time, the range hood is turned off, and the kitchen is still sealed. Because the air pressure in the kitchen is relatively low, the air pressure in the flue is higher than that in the kitchen, which leads to the situation of oil fume backflow. Therefore, some doors and windows can be slightly opened to form a pressure balance.

Third, the power is too small

If there is a restaurant downstairs, and it happens that the power of your range hood is not large, it will be easy to flow backwards. Because the power difference between the general commercial hood and the household is about four times, you can only change to a range hood with a higher power.