? "Equalizing" Tanks?

As long as the grey tank has more in it than the black tank, the flow will be from grey to black when equalizing. I've used the three valve system for years with no black back up into the grey tank. At least nothing that was visible in the clear drain section when dumping.

I would think if you equalize levels in the black tank and the grey tank you will soon have two black tanks which would not be very healthy when you expect the grey tank to wash out hoses at the dump station. Grey tank full? Use the campground facilities for showers or control the way you take showers to minimize water usage.

I equlize the tanks the easy way....
While hooked to a proper sewer I dump the black tank to the hole in the ground.

Then I dump the gray

Thus equalizing both tanks at EMPTY.

You don't need a third gate valve. Do this

1. Drain the black tank
2. Close the black tank drain valve
3. Hold the drain hose above the level of the tanks. I usually just fling it over my shoulder.
4. Open both valves. This allows the gray tank water to back flush the black tank, removing any stuff from the gate valve
5. Close the gray tank drain valve
6. Drop the hose and allow the black tank to drain.

You can repeat steps 3-6 as many times as you want, but once will do it.

Finish up by draining the rest of the gray tank and rinsing the hose.

cmoecmoe wrote:
I added this valve from Valterra and it enables me to open and close valves on individual tanks as needed.

Craig

I also use one of these. As well as preventing any nasty surprises when removing the cap, I use it to equalize the grey water tanks. This only works if your tanks are the same height and mounted on the same level.

The words you quote there look very familiar- as does the link above to a valve that simply screws on to the hookup- no modifications required.

In one of our early camping trips we had Water + Electric, but no sewer nor a tote. The gray tank filled up fairly quickly (and that's not unusual) while the black tank was much more empty. This crimped our style slightly on our last day.

So, I bought the valve at the link above- so that if we ever wound up with a full gray tank, we could use it to move some gray water to the black tank.

So far, the valve has worked perfectly by somehow keeping us from being stuck with a full gray tank and no sewer...LOL. Someday, I may actually use it as intended. :R :B

...and warning, these threads often have a hot debate break out between folks who are strongly outspoken and poor listeners about their phobia that the black water might touch their gray tank, and are unwilling to acknowledge that, soap + body oils + dirt + food particles + naturally occurring microbes makes for very nasty, germ-laden brew of stuff all by itself...

I added this valve from Valterra and it enables me to open and close valves on individual tanks as needed.

Craig

You've got the idea right. However, most folks also install an additional knife valve between the cap and the outlet. I equalize the gray tanks but don't involve the black tank.