Black Tank Flush Valve Clogged

[DBSMITH]

I have 2002 Holiday Rambler Endeavor and mt black tank flush valve is clogged. I removed the cover to expose the valve and tried to remove the valve to clean. What I found is this valve has a T connection that is preventing me from pulling it straight out. I don’t know where the hoses connected to the T go obliviously one end goes into the black tank but where does the other end go? Any ideas or suggestions as to to fix? See pictures below.

 

[Rene T]

Welcome to the forum.
I have never heard of a valve being on the black tank flushing system. This valve you are talking about is it a check valve or some type of valve that can be operated manually? Can you get to the backside of that wall to see more of what you’re up against?
Did you just purchase this RV?

 

[Ex-Calif]

Only a guess but two inlets to the black tank so it flushes from 2 locations?

 

[Gary RV_Wizard]

Yes, it is likely that flusher has multiple spray heads and thus a Tee in the plumbng. Also, some use the same inlet to supply both gray & black flushing, but I don't see a selector valve in that photo.

In any case, the solution is to remove the metal panel to get at the plumbing behind it.

As for the clog, odds are its in the spray head itself or possible the anti-siphon valve that is incorporated in the line somewhere. I'd bet on the spray head.

 

[DBSMITH]

Welcome to the forum.
I have never heard of a valve being on the black tank flushing system. This valve you are talking about is it a check valve or some type of valve that can be operated manually? Can you get to the backside of that wall to see more of what you’re up against?
Did you just purchase this RV?

It may be the check valve. I need to do some more tracing. I will to remove the front panel to see everything And looks a bit daunting. I am not sure where the check valve is but have a diagram of the system and it might be under the bathroom sink. I will work to find it when I am back in town.

Yes I just purchased the RV. so I am new at this. But everyone has been very helpful in explaining and helping.

 

[DBSMITH]

Only a guess but two inlets to the black tank so it flushes from 2 locations?

I am not sure. I will have to do some additional searching.

 

[DBSMITH]

Yes, it is likely that flusher has multiple spray heads and thus a Tee in the plumbng. Also, some use the same inlet to supply both gray & black flushing, but I don't see a selector valve in that photo.

In any case, the solution is to remove the metal panel to get at the plumbing behind it.

As for the clog, odds are its in the spray head itself or possible the anti-siphon valve that is incorporated in the line somewhere. I'd bet on the spray head.

 

[DBSMITH]

Removing the panel looks a bit daunting but I think your right it’s probably the spray head. I am also going to find the check valve to see if it is clogged. I don’t know if this flush valve supplies both gray and black tanks.

 

[Rene T]

The valve you are taking about under the bathroom sink is probably called a vacuum breaker. I breaks the vacuum when you’re done flushing and stops fluids from siphoning back to the inlet where you hook up your hose.

you say your flusher is clogged. If it is, you’re looking at the wrong end probably. You may have to locate where it enters your tank, remove it and and wash/clean the nozzle holes.


By the way, the hose you you for flushing should be a dedicated hose just for that. You don’t want to use it for drinking water

 

[viceprice]

I overcame this with a little more water pressure. Did not work at a dump site that seemed to have low pressure. Worked at home where the pressure was higher. Has been fine since