The newly replaced TOTO toilet smells back, and what is the problem

Whether the toilet splashes or not, the key depends on its water seal (the distance between the bottom of the toilet retaining water and the water surface), and the height and area of the water seal depend on the flushing structure design of the toilet. It is important to know that the height of the water seal directly determines whether there is a return odor phenomenon, and the sealing of the water can isolate the dirty gas under the toilet. The water seal standard of the toilet is 50mm, and better products such as TOTO have just the right water seal height, between 55mm and 60mm, and the slope of the inner wall of the toilet is also larger, so that while ensuring the hygiene of the toilet, it is not easy to splash water.