On the road and question black tank sensor

[ondaroadagin]

Go your local home improvement center, buy a gallon of super powerful vinegar, and add about half of it to about 5 gallons of fresh water in your tank before traveling. This acid won't harm your tank and will be very effective in removing/dissolving waste deposits on the sides and bottom of the interior. DON'T add baking soda as the two chemicals neutralize each other. Vinegar into water. Not water into vinegar. Science is refreshing! ;^) This also works fabulously in grey tanks as well, maybe better due to greases that accumulate!

[Gunta10]

Agree with all others. Flush, fill a little bit, travel so it sloshes, and empty/flush again. sometimes it is the Gray Tank if I leave it open for extended periods, sometimes the Fresh Water if I keep it empty for long periods and then fill. They are imperfect. If it stays consistent, then maybe get it checked out. We are full-time and find that in time, usually a couple of days, sometimes one week, it corrects itself. We have also cleaned out the tanks annually

Ultimately, I trust what I've done in emptying, or in the case of the Fresh Water, filling. For a period of time I kept track of how many days we can go on a trip until it is full or the water tank empty: 7-9 days with no hookups, not showering in the rig. Minimal dishwashing (use paper plates and cups). I watched the percentage each day, compared it against each tank's capacity, and learned to gain a sense of how long we can survive without emptying/filling.

It is imperfect, but it gives me some confidence if the tank measurement is getting kluge.

[ForteePlus]

Originally Posted by Daquenzer

.... I actually have more problem with the grey water tank not being accurate. Go figure.

A few months ago at the Top of Georgia Airstream Park someone told us to avoid bar soap because the chemical binders in the soap can coat walls of pipes, tanks etc. In the case of our beloved silver tubes, this means perhaps the tank gauges will be affected as well.

[gypsydad]

Originally Posted by ForteePlus

A few months ago at the Top of Georgia Airstream Park someone told us to avoid bar soap because the chemical binders in the soap can coat walls of pipes, tanks etc. In the case of our beloved silver tubes, this means perhaps the tank gauges will be affected as well.

See post 14. We had gray tank reading issues. We did fill the tank and added the solution in post #14. Seems to have helped clean/clear out. The Calgon is easy to get as is the Pinesol. We used the Geo method early on which also uses water softner. This seems to help clean and "lubricate" inside the tank. Time will tell, but all's reading good again, right now.

[foobar]

Originally Posted by uncle_bob

Hi

It's a two person process. One running the flush valve and the other monitoring the level. If you trust the sensor (and that's an if ....) the second person just watches that. If you don't trust the sensor, the monitoring gets a bit more fun ( use a flashlight and look down the toilet).

If you go with the flashlight approach, you may find it "useful" to turn off the flush when you do the level check. A lot depends on just how things are set up in your RV.

Bob

I have a 2022 Globetrotter 27FB Twin.

I have a victron multiplus/lithium/solar conversion and a pepwave cellular system installed.

The pepwave is networked with the victron system controller (the cerbo GX).

I swapped out my sealevel display unit for one that supports the nmea 2000 protocol (a subset of the can bus protocol). The cerbo supports the nmea 2000 standard too.

I also swapped my steel propane tanks for Worthington aluminum tanks with built-in tank level sensors. The cerbo GX supports the Worthington tank sensors via its resistive analog sensor interface.

After these changes, I can see all of my tank levels, including the propane level remotely on my phone. The cerbo also serves up a copy of the touch 70 display data on the cerbo's local ethernet address so I can see the tank data via the trailers wifi network even when cellular data service is not available.

So, when flushing the black tank, I simply connect to 192.168.50.20 on my phone via any web browser to see a copy of the cerbos tank level display screen on my phone. Makes it super easy to to fill up the black tank to 100% over and over again until the effluent runs clear without needing a separate person to monitor the tank level or repeatedly going inside to check the tank level.

I also find that adding 15-20% fresh water to the black tank after dumping helps clear out any remaining "stuff" as it sloshed around when traveling to the next campsite. We literally never fill up the black tank before the Grey tank is full, so consuming some of the black tank capacity up front is a non issue for us.