Sewer tank flush is blocked
I have a 2014 Rpod 178. No water flows when I hook up a hose to my sewer tank flush. I can't trace the line since it goes inside the floor and across the trailer to the curb side. Any thoughts on where blockages likely occur? I can see where the flush line enters the tank, so I can pull the hose out of the tank and check the spray nozzle for a blockage. Seems odd though, since I have never used the black tank for anything solid, only urine. Other possibilities? Is there a back flow prevention valve on the line somewhere that may be blocked, and how would you access it? Thanks for any insights you can provide.