full hookups?

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niget2002

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Josephine, TX
I've never stayed at a place that had full hookups. We have a site next month that does.

When the drain pipe is hooked up at a full hookup, do you leave the valves open all the time? Or do you open/close them each day to empty the tanks?
 

RNS

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No leave them closed and open as needed. You want some "liquid" in the black tank to flush the solids. Also opening the gray after the black helps flush the line.
 

NY_Dutch

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The black tank valve is never left open except to drain the tank when it's more than half full. The grey tank valve can be left open, although closing it a day or so before dumping the black tank is recommended so it can be used to rinse the hose.
 

Tom

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I've never stayed at a place that had full hookups. We have a site next month that does.

When the drain pipe is hooked up at a full hookup, do you leave the valves open all the time? Or do you open/close them each day to empty the tanks?
Do not open/close every day. The black tank needs to be 3/4 full to provide some "swish" when dumping, and to prevent build-up of material that doesn't adequately drain. If necessary, I'll occasionally add water to the black tank to bring it up to 3/4 full or so. Alternatively, I'll just wait until the level is brought up at future stops.

Unless you're staying in one place for a long time, leave the gray valve closed. Dump the black, then dump the gray to flush out the hose.

Oops, two folks gave good answers while I was posting.
 

Mark_K5LXP

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I tend to be somewhat conservative in the full hookup situation. I don't even connect the hose until I'm ready to dump. I figure why leave the thing out to get weakened by the sun or be damaged in some way. Plus it looks kinda tacky. Even with a full house of us and the grandkids I don't need to empty but once every couple of days so it just becomes a rote task to connect, dump, rinse and put away. Usually it's OK for the duration of the stay and I dump just so I travel starting with empty tanks.

Mark B.
Albuquerque, NM
 

Rene T

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After dumping the black tank you should add around 5 gallons of water to the tank to help break down any solids left behind after dumping. Going down the road will really help out also.
 

DutchmenSport

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Anderson, Indiana
It sounds like you are fairly new to the RV / Camping experience. Let me give you something to think about, that if you start practicing now and do it all the time, will always benefit you.

I am assuming your black and grey water tanks flow to a single outlet. If they do, then this is very simple, and the benefits are tremendous.

First, you need to purchase a Flush King type of valve that attaches to the end of the sewer outlet. A Flush King comes with a clear section of pipe so you can see what is being discharged from the tank. I always dump with a clear section somewhere in the hose line so I can see what's actually dumping, and how clean or dirty the tank still is.

So, with the 3rd valve attached, you can now back-flush the grey water tank into the black water tank and fush the black water tank out. The benefits are, the back flush works. It will pull a lot of "stuff" that sticks behind. Also, you are re-purposing the gray water a second time (which is going to be dumped anyway). And third, you do not need to add extra water to your black tank (via the toilet) to add to flush it out.

Here's how you do it.

3 valves.
Valve 1 is the Flush King.
Valve 2 is the Black Tank
Valve 3 is the Grey Tank

Open 1 and open 2 (Flush King and Black). Leave the gray closed. Dump everything out of the black tank until it quits running (you can see this with the clear section of pipe).

Now, close the Flush King (1) and open the grey tank (3). The black and grey are now both open. The Flush King will not let anything drain down out. When you open the grey valve, the water will back-flush into the black tank. Because the black tank is empty, nothing will force itself back into the grey tank.

Leave the grey tank valve open, count to 10 or 15 and then close it. This now closes off the grey tank so nothing will go into it.

Now, open the Flush King (1) again and let the black tank drain. Again, watching that clear section of pipe, you can see all the extra 'stuff' coming out that did not exit on the first dump.

When it quits flowing, repeat these steps again. Depending upon how much water you have in the grey tank, you can back-flush a couple times real easy, Sometimes, I can back-flush 4 times. I usually strive for 3.

Each time you do this, you are lowering the grey tank 1/2 the starting capacity.

So if there is 20 gallons in the gray tank to start with, 10 will transfer (back flush) to the black tank. Next half of the 10 will back flush Leaving 5 gallons). That will be enough to do a final rinse of the sewer hose. So the secret to flushing 3 or 4 times is to have a full tank of grey water.

If you do this EVERY time you dump your tanks, your tanks will not have odors, will always be flushed out good, and you'll never have any poo-build-up inside your tanks.

Do this when you break camp also. Then add a final 5 gallons of clean water back into your black tank and hit the road. The sloshing while driving will also help clean the tank out. Add a 1/4 cup of Dawn Dishwashing liquid, and your tanks will never, never smell.
 

Mark_K5LXP

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I've found that merely leaving the black tank valve open and alternatively opening and closing the gray allows a decent amount of "backflow" through the Y into the black tank to allow a few rinses before the gray is empty. Leave a bit in the gray tank for final hose rinse and no futzing around with extra fittings and valves. I do keep a "third valve" fitting in the kit in the event I want to equalize the two tanks and gain a bit of extra capacity for one or the other.

Mark B.
Albuquerque, NM
 

niget2002

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Josephine, TX
My hose has the clear elbows on it that I can watch.

The trailer has a black water flush on the back of it. So far what I've done is the following:

1) hookup up drain
2) Open black water valve
3) start hooking up blackwater flush hose
by now, the effluent is trickling from the blackwater tank
4) open the grey water valves and after a moment or so turn on the blackwater flush
5) watch the effluent until it starts running clear
6) close the blackwater tank
7) close the greywater tanks
8) disconnect the drain
9) turn off the water and disconnect the blackwater hose

My reasoning is that doing it in this order flushes everything pretty good and leaves some water in the blackwater tank to slosh around while driving.
 

HappyWanderer

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Much more effective to dump the black tank, then close the valve and turn on the tank flush. Fill the tank about 1/3 full, then dump again. Then use gray water to flush out sewer hose.

The “whoosh” of water flowing out of the black tank does a better job of removing residue than a trickle of water.
 

Larry N.

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Westminster, Colorado
I've found that merely leaving the black tank valve open and alternatively opening and closing the gray allows a decent amount of "backflow" through the Y into the black tank to allow a few rinses before the gray is empty. Leave a bit in the gray tank for final hose rinse and no futzing around with extra fittings and valves. I do keep a "third valve" fitting in the kit in the event I want to equalize the two tanks and gain a bit of extra capacity for one or the other.

Mark B.
Albuquerque, NM
I've done that for years.
Much more effective to dump the black tank, then close the valve and turn on the tank flush.
Not all rigs HAVE a tank flush. And the procedure Mark describes does indeed work as well, sometimes better than using the "Sani-Flush" or whatever brand. Since I have one on mine, I often do BOTH.
 

HappyWanderer

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Not all rigs HAVE a tank flush. And the procedure Mark describes does indeed work as well, sometimes better than using the "Sani-Flush" or whatever brand. Since I have one on mine, I often do BOTH.
The OP specifically stated that he does have a tank flush. Unfortunately, he’s not using it very effectively.
 

John From Detroit

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Apr 12, 2005
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Davison Michigan
Ever seen the adds for the useless take deodorizer chemicals? (Stinky RV stink coming off the roof pipe) Only time I have EVER had that happen..... Left a valve open the stink was coming out of the ground and out via the drain pipe.. Close the valves.
 
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