How To Clear Black Tank Level Indicators That Are Apparently Clouded Over

[CurtisWessel]

We have a 2022 337RLS. Two of the four black tank level indicators remain red after said tank has been thoroughly flushed/drained. Any clues as how to clear them?

[JM0397]

Saw an interesting idea the other day, from an off-grid blogger. Just before hitting the road, dump a 5lbs bag of ice down the toilet - and of course make sure you have some water in there already. Then drive, should help scrub things out a bit.

[CurtisWessel]

Thanks C&T; will give that a try.

[Scott'n'Wendy]

We have a 2022 337RLS. Two of the four black tank level indicators remain red after said tank has been thoroughly flushed/drained. Any clues as how to clear them?

You will find it is a never ending battle if you want your sensors to read properly. After the getting them clean - if you do- they will be back to a false reading next time you use the tank. We gave up on the black tank reading back in the 90's. And the OEM sensor tech has not improved since then.
If you want a decent sensor..try this
https://www.rvupgradestore.com/Garne...p/709-1003.htm

[Second Chance]

As @Scott'n'Wendy stated, the OEM sensors are notoriously unreliable and have been for decades. The ice idea has also been around for decades and is not terribly effective. If the outside temps are any warmer that the 40s, the ice won't last long enough to do any good. You can search for "geo method" for cleaning tank sensors on the forums or Google. This involves, in various combinations and quantities, adding clean water, a water softener such as Calgon or borax crystals, and a detergent to the tank before a travel day. There was a recent post on this forum by someone who spent their career in the soap and detergent industry who made a good case for using HE laundry detergent rather than the dishwashing liquid most of us have used for years.

Now, all that said, many of us have learned to just live with it and have learned to judge how long we can go before dumping. This is especially true of the gray tanks which don't have rinsers. I have always managed to keep the black tank indicators clean by using the following process: 1) drain black tank with rinser running; 2) when the effluent is relatively clear, close the drain valve and let the rinser run for another four minutes (we have a 53 gallon black tank, but this also worked on our previous Reflection with a 45 gallon tank); 3) after the four minutes, open the drain valve again and let the tank drain - still with the rinser running. When the flow gets down to the point that it's just the water from the rinser draining, turn off the rinser and wait for the tank to completely drain. If the bottom sensor is not clear, I repeat the four-minute flush again.

Finally, the SeeLevel tank monitors are a great solution if you want to go to the trouble of getting up in the bowels of the trailer (pun intended?) to replace the sensors.

Rob

[Keebler]

When I first got an RV with waste tanks and sensors, I was obsessed with checking them; now I almost never use the sensors. We now have a really good idea based on usage.

All that said, as mentioned above, more water is better. When I am on full hookups and have time; I do the process @Second Chance outlines above repeatedly until things are consistently clear.

The clear elbow is a great tool. I have upgraded to one that allows you to hook up a hose and spray water in from that end too; I add that as a final step in the rinse process.

[ajg617]

Saw an interesting idea the other day, from an off-grid blogger. Just before hitting the road, dump a 5lbs bag of ice down the toilet - and of course make sure you have some water in there already. Then drive, should help scrub things out a bit.

Tried that twice - didn't work. What did work for me is using the tank until it burped then doing what @Second Chance does once the tanks have emptied a bit and I watch the flow meter carefully and put about 20 gallons back in. A side benefit is that this process has removed some foreign objects that were preventing the gate valve from closing all the way three times now.

I've tried running 800 miles with 2/3 full figuring that would break things up a bit but all that did was leave the 2/3 full LEDs lit when we dumped and reduced my mpg some. I dump a bit more frequently when we are traveling a long distance over multiple days to a destination.

[Insist on live music]

Suggestions: use one of the legacy "wands" as often as possible (Camco RV Flexible Swivel Stik with Shutoff Valve). Use LOTS of water when flushing your #2 . . . hold flush pedal 10 - 12 seconds, occassionally through 1/2 cup liquid Dawn into a full black water tank, then rinse and lastly, run your Black Water Flush until clear - sometimes I run full 5 minutes.

[dryfly]

I use the "geo method" for preventing odor, and it works well for that but does nothing as far as cleaning sensors in my case. Like many, I've learned to live with with the lack of sensors in the black tank.

[Fivecodys]

As @Scott'n'Wendy stated, the OEM sensors are notoriously unreliable and have been for decades. The ice idea has also been around for decades and is not terribly effective. If the outside temps are any warmer that the 40s, the ice won't last long enough to do any good. You can search for "geo method" for cleaning tank sensors on the forums or Google. This involves, in various combinations and quantities, adding clean water, a water softener such as Calgon or borax crystals, and a detergent to the tank before a travel day. There was a recent post on this forum by someone who spent their career in the soap and detergent industry who made a good case for using HE laundry detergent rather than the dishwashing liquid most of us have used for years.

Now, all that said, many of us have learned to just live with it and have learned to judge how long we can go before dumping. This is especially true of the gray tanks which don't have rinsers. I have always managed to keep the black tank indicators clean by using the following process: 1) drain black tank with rinser running; 2) when the effluent is relatively clear, close the drain valve and let the rinser run for another four minutes (we have a 53 gallon black tank, but this also worked on our previous Reflection with a 45 gallon tank); 3) after the four minutes, open the drain valve again and let the tank drain - still with the rinser running. When the flow gets down to the point that it's just the water from the rinser draining, turn off the rinser and wait for the tank to completely drain. If the bottom sensor is not clear, I repeat the four-minute flush again.

Finally, the SeeLevel tank monitors are a great solution if you want to go to the trouble of getting up in the bowels of the trailer (pun intended?) to replace the sensors.

Rob

I do the same thing Rob but I use a flow meter on the hose so I can tell about how many gallons I'm loading into the black tank.

It's a crappy job but somebody has to do it!