Fullway termination valve

[MiCamper6]

Can anyone tell me what the 'fullway termination valve' is? Is it the valve at the drain where the slinky attaches? Thank you.

[nuthin_fun]

That's correct. On most trailers and coaches, it's the "T-handle" valve you pull to drain the tanks. If you don't open it while flushing, you will end up overflowing or pressurizing (if there is something wrong with your vent) the tank, which will make bad things happen!

[Flybob]

Short answer "Yes"
Long answer. The flush adds water to the black tank during the flush process and unless the black tank flush valve is open, it can overflow.

[MiCamper6]

Thank you for the prompt reply! Much appreciated.

[Billy55]

Please tell me what leaked? Second trip in our 2021 22ft Sunseeker.
2 nights. Leaving: drained black, drained brown. I have the see through at the ground. Hooked up long hose to the flush on the other side of the rv. Still saw some stuff going through, so kept it on maybe 5 minutes. Stopped flowing and started leaking below the rv under the same area as the flush connection.

First trip was one night a month earlier. Leaving: drained black, drained brown, filled potable. Saw the hose that came with was too short to go to the other side of rv to hook up to the flush. I knew I didn’t need it anyway.

[Billy55]

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