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Cleaning RV Holding Tank Sensors

Fixing and Cleaning Your RV Holding Tank SensorsIt's a common tale, you dump your black tank and as soon as you're done you go back into your RV only to find that the tank levels are still reading "FULL". If this hasn't happened to you, it's only a matter of time before it does. It's very common to find your Black Water holding tank sensors reading "FULL" (or partially full) all the time.

Before you start beating yourself up for not properly maintaining your waste water systems, you should know that this is a very common problem that most RV users encounter from time to time. Thankfully, fixing this problem can be very simple and inexpensive.

Let's start by understanding what is causing your sensors to misread, then we'll talk about solutions to this problem.

There are two primary reasons why your tank is reading "Full"

  1. The sensor probes inside your tank have debris or waste on them that is causing them to report that your tank is full all of the time
  2. Your sensors are broken or malfunctioning and need to be replaced

If you've successfully attempted to clean your sensors and they still continue to read "FULL" then you can probably assume that either the sensors are too dirty to restore or that they are broken and will need to be replaced.


So, how do you clean your sensors?

To clean your sensors you'll need a good cleaning product that will break down the waste that is resting on your sensor probes.

Unique Camping + Marine's Sensor Cleaner is an eco-friendly cleaner that is specifically designed to remove the debris that may be causing your Black Water sensors to read “FULL” all the time. It uses a blend of active probiotic cultures and enzymes to quickly break down waste, allowing your sensors to read properly.

Cleaning your sensors with Sensor Cleaner is quite easy, but before we go over the steps you'll follow, you need to understand that Sensor Cleaner can not repair broken sensor probes. See the bottom of this page for more info on this.

If your sensors are broken or malfunctioning, simply cleaning them won’t solve your problems. They will need to be replaced.

Understanding this is very important because the majority of the time when customers report that Sensor Cleaner didn't work for them, it's not because Sensor Cleaner didn't do it's job. It's job is to clean the sensors probes and its very likely it cleaned them very well!

It's very likely that the real problem is that their sensor probes are either broken or malfunctioning and need to be replaced.

Now that that's out of the way....

Here are the steps you'll need to follow to get your sensors back on track:

  1. Close your Black Water valve and fill your Black Water tank with enough water to reach the misreading sensor. (If the water isn’t high enough to reach the sensor probe, Sensor Cleaner will not be able to clean it.)
  2. Shake Sensor Cleaner well then pour 16 oz. (half of the bottle) down your toilet.
  3. Allow Sensor Cleaner to work. For Sensor Cleaner to break down the waste that is resting on your sensor probes it takes several hours to fully work. Allow for 12 hours minimum before dumping your Black Water tank. It is possible that it may take up to 72 hours for Sensor Cleaner to fully clean the sensor if the amount of buildup is substantial. As a rule, give it as much time as you possibly can to ensure the deepest possible clean. It won’t hurt your tank to leave Sensor Cleaner in your tank for several days at a time.
  4. Agitation is very helpful to knock the debris loose from the sensor probes. If possible, drive the unit for several miles or rock the unit back and forth if driving isn’t an option.
  5. Dump your tank.
  6. Leave your Black Water valve open and perform a tank rinse (if possible) and rinse for 20 - 45 minutes to completely flush out the waste in your Black Water tank.
  7. Repeat if necessary.
  8. If, after two treatments, you are still getting misreading levels its probably time to consider replacing the sensors as they are either too dirty to restore or broken / malfunctioning.

If you've followed these steps you will likely find that your sensors have improved significantly (most people report that their sensors are completely restored!).

Nice work!

Don't get frustrated if it happens again down the road. As we said at the beginning, this is a very common problem that can afflict even the best of us!

If you need any further assistance, don't hesitate reaching out to us. You can always email us here. We're happy to help!

Good luck and Happy Camping!


Black tank sensors not working? Clean and restore RV holding tank sensors with Unique Sensor Cleaner.


Important: Please note, malfunctioning sensors can be a VERY difficult problem to tackle in certain rigs and unfortunately, in many instances, nothing can restore them - including high pressure cleaning or dangerous, caustic chemicals. Many sensors are simply beyond repair or restoration.

You might ask, "So, if there is some chance that Unique Sensor Cleaner won't work, why do you sell it?" Good and honest question! We know what a frustration it is to have sensors that don't read accurately and we know that many people are willing to try anything to get them restored - even if there isn't a 100% success rate - so we developed Unique Sensor Cleaner. Will it work every time? Unfortunately, no because some sensor probes are simply broken or beyond repair. But rest assured that Unique Sensor Cleaner is the strongest cleaner available to clean your sensors - so if they CAN BE cleaned, Sensor Cleaner will be the product that gets the job done.

We hope you have fantastic results in restoring your sensors, but again, please understand that our cleaner will only be effective for those users whose probes can be cleaned are aren't broken. Unfortunately, that is the simple truth. Is it worth giving it a try? We believe so, but you may disagree, hence our desire to be transparent and honest. If your sensors aren't restored after properly treating them with Unique Sensor Cleaner, there is a very good chance they are broken and NOTHING will be able to restore them. You will either need to replace them or learn to live with misreading sensors.