Why is it forbidden to use bell-type floor drain?

Because the bell-type floor drain has a small sealing height. The ice force condition is poor, and impurities are easy to deposit at the bottom, blocking the water flow channel. The bell jar (buckle bowl) is also easy to be removed, destroying the water seal.

The floor drain is the only channel connecting the drain pipe with the room. According to the WHO survey, the reason why SARS is widely spread in many places is that the sewers are connected in series, the floor drain is not completely sealed, and bacteria spread indoors through the drain, causing health problems. The shortcomings of the old bell-type floor drain are exposed.

Extended data:

Most families have encountered the odor of floor drain, as well as serious problems such as sewage overflow and insects crawling out. Because the floor drain is the connection between the sewer and septic tank and the living room space.

The old floor drain relies on the water stored in the floor drain itself to form a water seal, which separates the living room space from the piping system. However, the "water seal" of the old floor drain is easily destroyed. Once destroyed, sewers and even septic tanks are connected to indoor space without any barrier.

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