Fresh H20 leaking when backwashing

[Scheinin]

For the 5 years I have been on the road when I backwash my black tank I hook up the outside shower to the backwash,



Last week when I turned the water on it leaked out where these lines went up in the ceiling of my basement:



I shut the water off, cleaned up the mess, then turned the water back on. No leaks the rest of the time I cleaned the black water tank.

Next time I cleaned the tank, the same thing happened. I put a camera up the whole where the leak came from:



Could not see any disconnected hoses, or where the water was coming from:



Any suggestions?

[Scrapper]

Look for the vacuum breaker / back flow preventer. It can be located under the vanity sink or in the wall accessible through a panel on the shower surround. Sometimes they stick open letting water leak. They are always at least 6 inches above the toilet rim.


There has been several posts on this subject in the past, 2 or 3 within the last week.

[Scheinin]

Originally Posted by Scrapper

Look for the vacuum breaker / back flow preventer. It can be located under the vanity sink or in the wall accessible through a panel on the shower surround. Sometimes they stick open letting water leak. They are always at least 6 inches above the toilet rim.


There has been several posts on this subject in the past, 2 or 3 within the last week.

Found it. Next time I dump, I will check there for leaks. Access is behind my shower through a hole just big enough to get my hand. Don't know how I am going to be able to replace it without ripping wall.

Thank you.

[dieselguy]

The black tank flush vacuum breaker has been a leak source for several years on the Montana (SOB) line as well. As many owners just remove them and install a union (Shark fitting) at that point as replace the vac breaker ... just food for thought. Unless your black tank was 100% full and you removed the flush hose for some odd reason at that point ... the lack of a breaker would never be of issue.

[emm-dee]

Originally Posted by Scheinin

Found it. Next time I dump, I will check there for leaks. Access is behind my shower through a hole just big enough to get my hand. Don't know how I am going to be able to replace it without ripping wall.

Thank you.

How big is the access hole. Mine is on a closet wall adjoining the shower. It is a fairly tight fit but replacing the valve is not that difficult.

Once the plumbing police chime in you’ll have more info than you ever needed.