After the filter element of the water purifier is replaced, the waste water pipe does not drain. What happened?

From the point of view of Shui Sheng science and technology engineer:

First, it may be that the reverse osmosis membrane of the machine is not installed.

Second, there is something wrong with the solenoid valve of the wastewater discharge pipeline, which can't be opened.

Third, it is recommended to contact professionals for maintenance as soon as possible. If there is something wrong with the water purifier, it will affect the water quality and not purify the water.