Holding Tank Terminations
A coworker recently purchased a 2021 Prowler 271BR. He's telling me that his Black Tank valve must be open for him to be able to empty his Gray Tank. This does not seem correct to me. Is this SOP for ...
Forum Discussion
StarkNaked wrote:
There is nothing stopping someone from putting the plumbing together like this.
But... If the black tank is full, and the gray tank is empty, and the gray tank valve is opened, it means that the black water would back flow into the gray tank until they are both at the same level. So, half of the black water would be in the gray tank. Doesn't sound like a good thing!
Now before someone says you should never open valves in that order, never underestimate the possibility that it could happen.
IF the black tank works as normal, there is no way unless you did not take the cap off and put the dump hose on, could back flow into the gray tank
