Vent under bathroom sink

[Dale and Becky]

I am having trouble with water coming out of the vent that is under the bathroom sink of my 2013 Montana High Country 343rl. It is attached to the top of a white water/drain line that is coming up through the floor and there is another white water/drain line attached to the side of it (black vent) that goes back down through the floor.

[billr]

A couple things could cause it.

Grey tank full, usually the shower is the first place though.

Something is plugged up in the drain? May need to root it out.


The drain vent has a check valve in it. Could be bad. Replace it. the whole thing. They have them at Home depot.


Bill