Water coming out of roof vent!

[babock]

Originally Posted by TheWolfPaq82

That's how most of us do it. I then close the valve a couple times to backfill and flush out a little more. Always get some stragglers to come out on first or second backfill.

That's how I do it too. I run the black tank flush for quite a while until it runs clear before I close the tank valve to allow the tank to fill.

[myredracer]

Originally Posted by Semperfi24

My experience is that you are wasting your time if you leave the valve open.

Have you actually seen the spray pattern from the nozzles though? The nozzles are aimed so that they hit the tank bottom around 6" or so from the sidewall they're mounted on. They're not aimed at a wall. Gobs of TP and poo sticks mostly to the bottom of a tank and not the walls so you want the tank's bottom flushed to get the solids moving. You might be able to look down your toilet and see the spray coming out.

The spray pattern out of these things is pretty wimpy and only hits a small area around them. Once you get a little water on the bottom of the tank, the spray won't do much. As an example, take a kiddie pool, fill it up to about an inch of water and see if your garden hose sprayer can clean the bottom.

The inlet for our rinser has a label that says tank valves must be open when using the inlet. There's a reason for the warning. All it takes is some kind of distraction some day and you can end up with a disaster to deal with. You want the dump valve open so the sprayer can do what it is intended to do.

[plh869]

I wanted to clear up my miscommunication. Our RV does not have a built in back flush or sprayer. We purchased the “Flush King” valve that attaches to the clear elbow that attaches to the black tank. The sewer hose is on the opposite end of the “Flush King” valve. My husband closes the valve then has the garden hose attached to the elbow and flushed water into the tank with the “Flush King” valve closed. We will definitely try your suggestions of running the water into the tank with the valve open then closing the tank to allow it to fill. We always closed our valve and filled it with water with the timer going and never had a problem until this time. We’re thinking something such as toilet paper may have clogged the tank causing the water to go up the roof vent pipe. There wasn’t enough water in the tank to cause it to overflow as my husband had just started to fill it again. All of your ideas and suggestions are greatly appreciated! It’s all trial and error with camping and that’s what makes it so much fun!!!

[SlowrideHD]

Originally Posted by Semperfi24

My experience is that you are wasting your time if you leave the valve open. Maybe different RVs have different black tank flush "sprayers" and therefore make some more effective than others. But for me, if you leave the valve open and use the black tank flush, the sprayer gets it off the walls, but it just sits on the bottom of the tank and doesnt flow out the dump pipe.

So for me, when I see clear water, I close the valve and continue the flush. After a minute, I open the valve and the clear water is now gross again. If you close the valve for a minute, you are only putting 5-6 gallons in the tank, thats only going to be about 1-2 inches of water at the bottom. Deep enough to pull all the debris from the bottom, but not deep enough to hinder the flush sprayer. That rush of water movement when you open the valve is the key. The flush sprays it off the tank walls, and the sudden rush of water exiting the tank moves it out. But I dont presume to know whats best for anyone else, I just do what works for me and my set up. And for me, the only way to really get the tank flushed out is a combination of what JohnD10 said (flushing while dumping) and then also closing and opening the valve a few times at the end

Pretty much what I do. I usually dump my kitchen sink grey tank first to get some soapy water down through the dumping hose. Makes it wet and slippery. Then I dump my black tank fully. I have a green dedicated hose that I hook to my black flush and I turn it on (with the black dump valve open) and let it rinse for 5-10 minutes while I do other stuff. Then I start closing the black dump valve and let the tank fill about 1/4 of the way (guesstimate) and then open the black dump again. I do this quite a few times until no more traces of paper or anything else is seen through my clear elbow. As a side note....I watched a demonstration of tank dumping using a clear tank with a mix of solids representing black waste. Nothing flows across the bottom of the tank to move solids until the water level got down to about 1/4 full. So to get the last remnants off the bottom, it really doesn't do much good to fill it more than 1/4 of the way each time before you open the dump valve. After being satisfied that I have got everything out that I can, I dump the last grey tank. I also add another 5-10 gallons of clean water to the blank tank and leave it. Before I pull out, I add about a cup of Pinesol and about 1/4 cup of Dawn dishwashing liquid right down the commode. That sloshes around on the way home, or to the next campsite and cleans the sensors and the tank really well. I sometimes put a little less of this mixture in my grey tanks to clean them but not as often. Never had a sensor problem or anything else.

[JohnD10]

Originally Posted by plh869

Our RV does not have a built in back flush or sprayer. We purchased the “Flush King” valve that attaches to the clear elbow that attaches to the black tank. The sewer hose is on the opposite end of the “Flush King” valve. My husband closes the valve then has the garden hose attached to the elbow and flushed water into the tank with the “Flush King” valve closed.

If the tank's valve is closed, then water from the Flush King can't get back into the black tank.

[Jfkmk]

Originally Posted by JohnD10

If the tank's valve is closed, then water from the Flush King can't get back into the black tank.

I was kinda thinking the same thing.

[TheWolfPaq82]

Originally Posted by Jfkmk

I was kinda thinking the same thing.

The hose port is ahead of the valve. Shutting the valve prevents the water from running back into the dump hose and the water is trapped and backfills the tank.

[Jfkmk]

Originally Posted by TheWolfPaq82

The hose port is ahead of the valve. Shutting the valve prevents the water from running back into the dump hose and the water is trapped and backfills the tank.

Ok. So I guess it wasnt the actual black tank valve they closed.

Since all this does is fill the tank from the discharge side, would go it be easier to just fill it from the toilet?

[Reverse_snowbird]

Originally Posted by Jfkmk

Since all this does is fill the tank from the discharge side, would go it be easier to just fill it from the toilet?

That's what I'd do. Just fill up the black water tank up a couple of times and dump each time.

If you need bit more cleaning ability, get a wand similar to this one https://smile.amazon.com/Valterra-A0...s%2C182&sr=8-3

[rlh1957]

Black tank back flush hose on and dump valve closed... you are filling your black tank essentially... it is like a pressure wash inside... but that black tank fills up.
So lucky you only has water coming out the top vent which is higher than toilet. Usually the toilet overflows into the RV. Stink water is one thing... but any water all over the floor will destroy a subfloor.

[gkochel]

Originally Posted by hinkle_e

I flush the black tank with the valve closed but always use a flow gauge/totalizer. If you know the tank size, you know how much water you can put in before it'll ever become an issue. If you know how much you are putting in...no issue. $15...never flush without it.

The gauge is a good idea or you could just set the alarm on your phone for 10 or 15 minutes ( should get it to about 3/4 tank ). You can test it first to where the 3/4 light comes on and then use that as the time to open the valve up. With 3/4 of a tank the variance between campgrounds with water pressure won’t be a problem. I have been doing that forever and it never filled all the way up but had a good swoosh out.

[762vram2043]

Originally Posted by Semperfi24

My experience is that you are wasting your time if you leave the valve open. Maybe different RVs have different black tank flush "sprayers" and therefore make some more effective than others. But for me, if you leave the valve open and use the black tank flush, the sprayer gets it off the walls, but it just sits on the bottom of the tank and doesnt flow out the dump pipe.

So for me, when I see clear water, I close the valve and continue the flush. After a minute, I open the valve and the clear water is now gross again. If you close the valve for a minute, you are only putting 5-6 gallons in the tank, thats only going to be about 1-2 inches of water at the bottom. Deep enough to pull all the debris from the bottom, but not deep enough to hinder the flush sprayer. That rush of water movement when you open the valve is the key. The flush sprays it off the tank walls, and the sudden rush of water exiting the tank moves it out. But I dont presume to know whats best for anyone else, I just do what works for me and my set up. And for me, the only way to really get the tank flushed out is a combination of what JohnD10 said (flushing while dumping) and then also closing and opening the valve a few times at the end

I do about the same but also vary the flow rate of water to the black tank flush fitting toward the end of the process. I slowly vary flow rate up and down from full to low flow several times after discharge from the tank runs clear and this always gets more TP and turds out. Apparently the flush stream in my tank hits different areas of the tank sides, bottom at different flow rates.

When done flushing I also close the dump valve and let the tank flush flow continue for about a minute to put 3 to 5 gallons of water in the 35 gallon black tank so there's some sloshing action in the tank as we tow to next park.

[tjwdj]

Actually, I leave my valve closed when back washing....after the initial dumping. I watch to ensure it does not overflow by checking the toilet; I can see the back wash flow and can tell when it's getting close to full. Never had an issue.

[RacerRalph]

Originally Posted by Jfkmk

Ok. So I guess it wasnt the actual black tank valve they closed.

Since all this does is fill the tank from the discharge side, would go it be easier to just fill it from the toilet?

Refilling via the Flush King is easier than sloshing 5 gallons of water in to the toilet three or four times. With the clear window it is easy to see when the black tank is "Clean. During my once a year flush, t take a couple times to get "clear" liquid, but another couple times until the TP clears out. Takes ten minutes of so.