Waste Tanks and Hook Ups

[Tarfu]

When staying at a campsite with full hook ups, do you leave the tank valves open all the time or do you let them fill up and then drain?

I could see letting the black tank fill in order to get a good chance of emptying the solids....

Also is it possible to open the grey tanks to allow them to flow onto the black tank?

I have a 2002 Sprinter.....thanks Bill

[GaryWT]

People do things differently but the one thing everyone agrees on is to leave the black tank closed and don't dump until at least 2/3 full. I will add water to dump if it is not full enough. I generally open my grey tank when I hook up and close it the night before we are leaving to collect some water to dump after I dump the black tank. We can fill the grey tank in a day/day and a half after 2 or 3 showers and some dishes. For this reason I leave it open. Some will leave it closed to prevent orders or whatnot but we have never had an issue. Just be sure you have water in all the traps. Good luck and have fun.

[Ken / Claudia]

Your question about the gray water filling the black tank. They are 2 different systems and cannot fill each other, at least in all rvs I have had. They flow thru the same drain pipe at the last tee were the dump valve is located. Before that point they should not be any cross contact.

[Tarfu]

Thanks for the input....I will fill the black 2/3rds and run the grey open until the day before I leave to flush the system with....and never will the two systems co-mingle...Bill

[randy69]

just a quick thought ... The day before you leave your spot I shut the gray just to to fill up a bit. And after dumping the black, I dump the gray to wash out the sewer hose.

[Tarfu]

10-4...will do thanks for the tip..