When decorating the check valve reserved at the smoke crossing, the decorator may simply stick the periphery with glue, and cracks are easily exposed around it. No matter how good the quality of the check valve is, smoke will still come in from there.
The solution is to clean the check valve or replace it with a new one. When installing the check valve on the wall, it must be sealed well, and the surrounding area must be firmly bonded with sealant or adhesive. The flue opening cannot be changed at will, and must be opened in the auxiliary flue. Check whether the smoke exhaust pipe is deformed and twisted, and clean it in time or choose a suitable length.
In fact, it is very simple to solve the problem of backward flow of extended data range hood. As long as a lampblack valve is installed at the outlet of the lampblack machine, which is tightly closed and properly opened, it will not be blown away by the wind of the lampblack machine or sucked away by the negative pressure of the flue, and the backflow of lampblack and poor smoke discharge can be eliminated.
Due to the structural reasons of the check valve and the closing valve commonly used in the smoke outlet, it is impossible to ensure that it is "tightly closed and properly opened", which is also the reason for the frequent occurrence of oil fume backflow.
Suggestion: Since all range hoods are equipped with check valves, backflow will still occur after sealing valves are installed at smoke outlets, so electric smoke exhaust valves can be installed. Because the electric fumigation valve uses an electric switch, it is not afraid of sticking oil, and the sealing effect of positive and negative pressure reflux is the same. Patented electric fume valve can be found on the internet, which has a good effect on completely solving the problem of fume backflow.