Cleaning Black Water Tank Sensor

[Buddy]

Originally Posted by travelin' texans

This our 3rd 5er with same type of indicators none of which have worked worth a d#@n after a couple fills, black always shows 2/3 & greys show 1/3. After fulltiming several years, have learned the sound of black tank at flush when it is getting close to full, don't pay attention to indicators.

I USE CHEMICALS AND FLUSH A COUPLE OF TIMES AFTER LEAVING A CAMP GROUND. Indicators always worked properly. Also use proper toilet paper from Camping World, blessed to have on by me.

[Oregonbound]

Originally Posted by Adamsvr

Water, water, water, water... and more water. For the grey tanks, buy a back flush valve... then fill your tanks several times (usually takes about 5 minutes per fill.)

Adam, not sure what you mean by "Black Flush Valve". Wondering if it is the same as the black tank flush that is already installed or an additional piece of equipment.

What (temporarily) worked for me was to stick a high pressure spray wand (with a nozzle you can aim) down the toilet and clean all sides. When I did this I did see some TP flush out and then the sensor reading went to empty. I've heard the sensors are lag bolts. They are notorious for not completely getting seated against the inside of the tank or loosening up and then loosing their flush seating against the tank.

My guess is that this is what is happening - toilet paper is getting stuck on the unseated lag-bolt sensors so even though I cleaned it thoroughly, the next time it filled, tp again got caught there and constantly shows 2/3 full.

Of course, without going in there to examine more closely, this is only a theory.

[Adamsvr]

Yes, it's an additional valve with a hose attachment mounted on it. You attach it to where your exit point to your tanks attach to the sewer hose and then back flush your tanks. The valve is available at most RV dealerships or at Camping World.

[Oregonbound]

Wow...ok. Good to know. Thanks Adam

[atom ant]

I actually never thought of doing that for the gray tanks - good idea!

Maybe because we only part time and things get a chance to dry out, but I've never had the sensors stop working on any of my rigs. Not saying they are high quality, but just lucky I guess.

[rcflame]

The one I have is like a clear elbow that has a dump valve and a garden hose connection above the valve. It connects to the sewer hose connection on the trailer, and than the sewer hose hooks on the other end. Put it on with the valve closed, connect the sewer hose, and turn on the garden hose. It back fills the tank. You have to be careful and not overfill the tank or you can burst it. Open the valve and drain the tank. It helps to flush the tank. It helps, but not the cure all.

[atom ant]

Originally Posted by Oregonbound

Wow...ok. Good to know. Thanks Adam

And an even better picture!!

[Oregonbound]

Thanks Atom…couldn't decide but…with that…it's settled

[atom ant]

If you reduce the size a bit to reduce the height of the picture down a little, it will stay fixed within the window. As it is, it is just a little big and the scroll bar gets activated on the right so it can't all be seen at once.
Mine is right over the limit so I get the scroll bar, but the pic doesn't move.Edited by: atom ant

[hoosierguy]

Originally Posted by Oregonbound

After one draining black tank back to showing 2/3 full when completely empty. Have ordered an LST product to clean sensors but have my doubts. Of course will let folks if it works though.

I have noticed the same issue. I started using the black tank flush system to refill the tank (at least to 2/3 full)at least 2 to 3 times (up to 4 times)to get the tank to empty. After refilling and emptying, I turn off the black tank flush and check the indicators. I continue this process until the indicator show empty.

[Oregonbound]

Originally Posted by hoosierguy

I have noticed the same issue. I started using the black tank flush system to refill the tank (at least to 2/3 full)at least 2 to 3 times (up to 4 times)to get the tank to empty. After refilling and emptying, I turn off the black tank flush and check the indicators. I continue this process until the indicator show empty.

Just FYI - possibly a better method. I mentioned earlier that I bought a nice (but inexpensive) pressure sprayer / spray wand at Wal-Mart. It attaches to a hose and has a swivel/angle nozzle.

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I stuck this down the toilet and used this to spray all sides of the black tank. Worked well on the first try.</span>

Next, I'm going to find a fitting to connect the sprayer and short hose to the bathroom sink faucet - didn't like having to drag hose in from outside.

[Oregonbound]

I meant to mention that the spray wand/ pressure sprayer is a "Bonaire - Wash and Spray" from Wal-Mart and has a soap dispenser built in.

[rcflame]

On our 36RL the line from the toilet to the tank isn't straight. It has about a 45 degree bend that would make getting a want down to the tank difficult or impossible.

[Oregonbound]

ahhh...for sure. I know that there was a flexible wand specifically made for that set-up at Wal-Mart as well.