[TenOC]

Years ago I was at a campsite and the neighbor complained about that the after the kids had visited for the weekend that water was backing up in the shower. It turned out that the cable to open the drain valve had broken and the drain valve was not open. Are you SURE the valve is open?


One other time we purchased a used RV. On the first trip after boondocking a few days the black tank would not drain. While discussing the problem and solutions for a few hours, all at one the tank drained. We THINK that the previous owned had not completed drain the black water and the S*** had dried up into a "brick" that clogged the line. After a while the pressure forced the brick clog down the drain. We never had the problem again.


Have you tried "RidX" or a more aggressive acid treatment for clogged sewer lines?