Forum Discussion

Explorer

May 05, 2013

Bathroom flood - What did I do wrong?

We have a 2008 Newmar Canyon Star. Yesterday was our last day on the road home from Florida, so I wanted to empty the gray and black tanks. First I opened the black tank dump valve, and let it empty. I then opened the gray tank dump valve, and let it drain. Next I turned on the black tank flush valve, both dumps are open. While I was waiting for the black tank flush, I turned the fresh water intake valve to the "fill tank" position. I wanted to make sure we had at least half a tank of fresh water. After a few minutes, my wife came running out, yelling the bath room was flooding. I shut off both water hoses, and went in to find water all over the floor. The top drawer of the vanity was very wet. I could see water running down, what looked like a vent stack,( 2" black plastic pipe"). After I mopped up, everything seem normal. The water appeared to be clean, not gray water. I can't figure out what caused the flood. The fresh water tank was not over filled.

Class A

23 Replies

SolidAxleDurang
Explorer II
May 05, 2013
Atmospheric vacuum breaker. That's what's in your vanity. It's likely faulty.
J_Walker
Explorer
May 05, 2013
The black tank may have been stopped up or the valve actually closed. Right after the incident you probably would have found the black tank to be full if you checked.
Jim
Explorer
May 05, 2013
If you're sure that the black tank was empty when you turned on the flush valve, I'd think that the flush head inside the tank is aimed at the vent pipe. Sometimes the factory won't bother to weld the vent stack, or, they've been known to leave the vent stack with disconnected unions.

Other then that idea, I'm at a loss of what might have happened.