Fix your RV tank sensors

Codi JohnsonRV Tech Tips

Many of you have asked about cleaning your tank sensors. Well, sensor issues are fairly obvious: particulates, which could be toilet paper amongst other things. There are 3 sensors, which are essentially probes sticking inside the tank. Since the probes protrude inside the tank, we fill it up which leaves solids sitting up top. As we begin to release the water, we open the black tank, and as water exits we end up with solids that stick on top of the sensor. Typically it will be toilet paper, as toilet paper wicks water so it fools the sensor into thinking your tank is two thirds full when it isn’t

Now the question is, “How do I clean the sensors?” Now, in the past I’ve discussed Unique RV Digest-It and how it breaks solids down, but sometimes you need a little bit more help. So, Unique also makes an RV tank cleaner, which is about 15 times stronger than the Digest-It. What you’ll do is simply pour the contents down the toilet, fill the tank with water and allow it to sit overnight. This will break down all the solids and clean around the sensors. Now, is it 100% guaranteed? No, because you may have different particulates built up around the sensors, but for most of us this is going to be sufficient. 

Let’s back up. If you have the internal probe sensors, the Unique Tank Cleaner will be your best option. But, if you have something like sea level, where your sensors are located on the outside, a tank cleaner isn’t going to take care of the problem. External sensors have a tendency to pull away from the tank, so it becomes a matter of resealing them. 

Now, there’s some talk floating around about flushing ice down the toilet. Here’s the problem with that: ice has to cross the sensors, which means you have to move the ice, otherwise it just sits still. The hardest part is knowing how much water we have in the tank and knowing how much ice to use; too much, the ice won’t move at all, too little will melt. While there are some success stories involving the ice method, it’s really more the luck of the draw. Not only that, but you’re unable to clean all three sensors. Remember, you have one at one third, one at two thirds and one at capacity, which means you would have to drive like a maniac to move the ice around sufficiently. 

So the best thing to do is to purchase a product that will help the bacteria, but also thoroughly clean the sensors. Again, Unique has an excellent tank cleaner, and you can purchase it from their website or your preferred shopping location, and be sure to avoid chemicals that will harm the bacteria in the tank, like Draino, because it will kill the bacteria and you’ll end up with a repeated solid waste problem.

And there’s your Tech Tip!  

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