We have a 212QB and when the black tank is not even close to being full the odor comes up when you flush. The vent on the roof isnít obstructed in any way. If anyone has had this problem before I could use some advise on what to do. Will be looking into getting some type of scope to look around inside the tank when we get home.
The fan is off and the vent is closed so I dont think thats an issue. When we get home from this trip I think I will get an inspection camera from Harbor Freight or Amazon. Hopefully I can mount the camera on a 90 degree angle on a stick to see inside the tank. If the pipe has slid down I will need another person to pull it up while I watch on the camera.