The evaporator drain is suppose to drain off the condensation (water). If you plug the drain the water will end up inside the cabin on the floor.
The salt will drain out its water and end up killing it. it causes plasmolezed
well at the end of the day they drain the pool then in the morning they fill it up
If you have a plugged AC condensation drain, clear water will back up and end up on the passenger floor. If the heater core is leaking engine coolant you will have engine coolant end up on the passenger floor.
They are there so that the water that flows out the overflow skupper runs down and into the drain. When the drain pipe is mounted they end up sealed into the area between the inner and outer bowls of the sink.
I would say that if water had never backed up in your floor drain, then backed up even after you had the drain line snaked, Roto-Rooter didn't do their job. Once a drain line is cleaned, it should drain like it did before the stoppage. As for plugging the floor drain, it is there for a reason, I would not plug it. There are several items manufactured that will allow a floor drain to drain but if the line starts stopping up they will seal the drain off to prevent water from coming out of the drain.
if the drain is clogged up, then maybe
The evaporator drain allows condensation from the ac unit to drain. When the drain clogs up water will go into the passenger floor instead.
Because both sides of your sink are connected to a common drain line, and the common drain line is slow.
Please re post your question. What air pipe,are you talking about the breather vent inside the wall. If you are talking about the breather vent,it is not getting sucked up it is from water being backed up in your drain,and the water can not drain quickly enough, the drain needs to be cleaned.
Standing water is caused by the drain being plugged up.
The drain from the washer to the main line is getting plugged and the floor drain is easier. Drain cleaner in the floor drain should take care of it.