Originally Posted by 97Powerstroke
Kinda new to RV'ing... I bought a 2007 Rockwood Signature Ultralite 8244S fifth wheel. On the tank level annunciator panel, it has a "galley" tank and a "grey"tank level. I only have one grey water drain valve on the outside. So I'm guessing both drain into a common drain and there is a check valve somewhere keeping the shower from back flowing in the kitchen sink?
Even if they both did drain into a common tank the shower drainage would not back up into kitchen sink unless the tank was full.
My guess is you have two waste tanks "black" and "grey"
If you only have one sewer outlet and two pull handles its assured.
Otherwise you'd have two sewer outlets and three pull handles.