It is necessary to install the flue check valve.

What is the flue check valve?

The flue check valve refers to the valve that automatically opens and closes the valve plate by the thermal flow of the range hood to prevent the oil fume from flowing back, also known as the flue check valve, smoke prevention treasure and flue isolator. The flue non-return valve belongs to an automatic valve, its main function is to prevent the oil fume from flowing backwards, only allowing it to flow in one direction, and preventing the airflow from flowing in the opposite direction.

flue non-return valve is generally installed and used in the flue of domestic range hoods, which is a hinged pipe cover door that can be opened only by gravity or spring, as shown in the figure.

Application principle of flue non-return valve:

The non-return valve works by the principles of aerodynamics and lever mechanics. One end of the flue check valve is connected with the air duct of the lampblack machine, and the other end is connected with the public flue. When the lampblack machine starts to work, the air flow with lampblack pushes the check valve piece through the air inlet and the diversion curved surface to discharge the lampblack into the public flue; When the range hood stops working, the one-way valve will automatically close under the action of gravity, which will isolate the oil fume channel from the public flue, so that the oil fume in the public flue will not flow backwards.

Function of flue non-return valve:

The main function of flue non-return valve is to prevent oil smoke from flowing backwards. Many owners find that the kitchen without non-return valve often smells the cooking oil smoke of the neighbor's house, because the flue of the residential apartment is used for * * *. If the non-return valve is not installed, the cooking oil smoke of other people's house will reversely flow into the kitchen through the original exhaust pipe, causing oil smoke pollution.