Shower and bathroom sink grey water tank.

[Steelworker]

Because my bathroom grey water tank fills in 2 days is it ok to leave the dump valve open all the time? We are connected to a permanent sewer in a park model unit. I have heard that you should not leave them open any feedback on this thanks.

[chuckster57]

Bathroom gray should be ok to leave open. You may eventually get enough soap residue to make the sensors worthless.

[MarkEHansen]

I'm not aware of any downsides to leaving the gray valve open (others may), but one thing is that you need sufficient gray water to assist in the flush of the black tank through the dump hose. When you're planning to dump the black tank, you'll want to make sure you close the gray valve enough in advance that you have sufficient gray water to aid in this dump/flush.

[JRTJH]

An "alternative" to closing the gray valve and accumulating "used soapy water" to use when flushing the black tank is to close the gray valve a few minutes before dumping the black tank, filling the gray tank with clean water (actually flushing the gray tank) and when it's full, then go about dumping the black tank, flushing it, then using the "cleaner gray water" to flush the sewer hose. While it may be "somewhat wasteful" it will help remove any "sour smell from the gray tank, especially if you add some dawn to the water to help "flush and clean" the gray tank.

As for leaving the gray tank valve open while connected to campground sewer, there's no downside as long as your P traps, HEPVO traps and vents are functional. If you have a issue with any of them, you could get campground sewer gas migrating through your sewer hose, through the tank, up the drain lines and into your trailer. If that's happening, you'll know it soon enough. If you don't smell it, you don't have a problem. To "combat" that, form a P trap with your sewer hose, so a part of it is filled with gray water and that will prevent sewer gasses from migrating up the hose.

[sourdough]

I've tried up but won't leave them open. I went for about 3-4 months when I first started camping for longer time frames and thought it was nice not to have to mess with dumping every 4th day on our first trip. Trying to remember to save water in the gray tank to help clean out the sewer line after dumping the black tank didn't always happen but ran the black tank rinse "thinking" all would be OK - it wasn't. When we went to leave I disconnected the sewer hose to pack it up; it weighed about 5 times what it should so thought I had excess water in it; nope, nothing came out. Looked inside and the bottom of the hose with the ridges was completely full of
"goo" from soap scum buildup etc. which wouldn't come out. Bagged it up, threw it away and bought a new one. Haven't done it since and haven't had a clogged sewer hose since. I think they do make some hoses now that have a smooth interior so that may help but I've resigned myself to pulling the handles every 4th day....:(

[bobbecky]

Because my bathroom grey water tank fills in 2 days is it ok to leave the dump valve open all the time? We are connected to a permanent sewer in a park model unit. I have heard that you should not leave them open any feedback on this thanks.

If this is really a Park Model unit, why does it have tanks? If all your plumbing fixtures are residential type fixtures with p-traps, and the toilet has a water tank for flushing, you should be able to not need valves closed. This would be just like a sticks and brick home.

[bob91yj]

We are stationary full timers, we leave our gray tank valves open all the time. With full hook ups filling and flushing the black tank with fresh water solves the hose flushing issue.

[wiredgeorge]

I camped in Utopia TX a couple weeks ago and hook up my sewer hose. Left the galley gray tank open but the main gray (bath sink and shower) and black closed. Main gray was for washing things out while dumping the black. We had fire ants crawl up through the slinky stinky through the hose and ended up looking for something to eat in our kitchen drain. Guess the sewer that we were using hadn't been used in awhile. Suggest you at least run a tank or so through the sewer system for this reason; after that, likely OK as you probably drowned anyone living in the sewer.

[bob91yj]

I do form a P trap with my slinky hose to keep the sewer smells out. The hose gets flushed out with water from the washing machine almost every day so it doesn't get smelly.