[rrl1954]

coach # 462 after a few (2) FAST showers and some toilet use (1) person holding tank reads full and starts coming up threw shower .i can dump the it will read full but same thing happens . fresh water tank holds so no leaks into black tank

[HoosierDaddy]

Are u hooked up to city water?

[Fulltiming]

#462 should have a 160 gall waste tank (combined black and gray water). A full tank will take some time to empty. Have you had this coach for some time? If not, there are TWO valves that must be open to drain the waste tank on a Newell. The (typically) air powered valve and a (typically) manual drain valve between the air powered valve and the waste tank. To drain the waste tank, both of those valves must be open. If they are open and mess is backing up into the shower there must be a plug somewhere and that is a bad thing.

[Richard]

I am with Micheal if this coach is new to you. Newell uses a unique setup on the waste tank dump valves that is counterintuitive until you stare at it for a minute. The manual dump valve closest to the waste tank must be open. The air powered valve must be closed. Just as Micheal said. That allows black water and grey water to accumulate in the waste tank. The accumulated waste drains when you open the air operated valve.

The plumbing is somewhat hidden in that it is hard to see that ALL grey water enters the waste tank from the tee fitting on the downstream side of the manual dump valve. All black water flows directly into the waste tank.

You can arrange the valves to permit gray water (shower) to bypass the waste tank. Close the manual valve closest to the tank, and leave the air operated valve open. All grey water will drain constantly, and all black water is now held in the tank. .

[bestgenman]

To add,  if you use the PS dump, there is only one valve.  It is visible from the aqua-hot bay and is air operated as well.  The outlet turns down and should be capped.  It is accessible from the underneath and is not beyond arm’s length reach.
Since no two Newells are alike, you may not have a PS dump although I have never seen one without.

[Latitude 28]

Richard has posted on this one before.  A side note on the PS air operated dump valve; In addition to the dump switch in the AQH bay another dump switch is located in the cockpit overhead panel (wink wink).  On our coach that dump valve had not been used in a while and was frozen shut   At least two occasions, I could have used the PS dump valve in a state park that had a dual lane dump station.  We had to wait on other campers, all the while the left dump lane was wide open.  Needless to say I made a concerted effort to get that valve working.  All in all I have to say Newell really thought about giving an owner some options with the waste tank.

[Fulltiming]

Additionally, use of the dump switch in the cockpit (mine is on the dash) requires that the ignition be turned on before it will actuate the curb side valve.