Pete’s RV-TV YouTube Channel Resident RV Expert Randy Murray discusses a multitude of ways to clean your gray/black water holding tank sensors, clearing all inaccurate monitor panel readings from your camper. Sometimes you may get a full tank reading on the monitor panel inside your camper even after you’ve dumped your gray and black tanks.

Randy notes that this is generally caused by a build up of waste materials or anything that might have made its way down the toilet. These items can block the sensors preventing the correct read out.

Randy provides a few preemptive approaches to make sure you won’t have to deal with that faulty reading. The first is making sure before you flush that you add extra water so the toilet paper (making sure you use RV toilet paper) won’t clump up or dry out to the inside of the tank walls, the next is making sure the tanks are as full as possible (making sure not to overfill) before they are dumped.

Randy suggests the use of a tank flush chock to assist in filling your holding tank before it’s dumped. The good news is that there are other tools for when all else fails.

The first one Randy recommends is what’s called an RV swivel stick, which he explains attaches to a hose and sprays around water at a high velocity to break down any tank buildup. Depending on whether you own a travel trailer or fifth wheel, a longer flexible version is available for the harder to reach holding tanks.

Lastly, filling up a 5 gallon bucket with hot water and pouring it down the toilet should help alleviate the issue by steaming away the blockage from the sensors.

Video Transcript for “How to Clean Your RVs Holding Tank Sensors | Pete’s RV Service Tips”

Hey guys, Randy with Pete’s RV TV again with you today. Another quick tip segment for you. Have you ever gone out on a camping weekend, and you’ve dumped your tanks after the weekend, and you come back into your camper, and you get a false reading on your black or your gray tank kind of like that.

Looks full and you know it’s not. You just dumped it. Well, I’m going to take you into the bathroom here in just a few minutes, and I’m going to show you a couple of tricks to alleviate that problem for you. So let’s go take a look into a bathroom.

Alright, so here we are in a bathroom at one of the RVs we have here at the shop at Pete’s RV Center. Kind of an awkward place to have a conversation or shoot a video, but here we are anyway. Good information. So as I was mentioning earlier at the monitor panel, you know you’ve dumped the tank but it’s still reading full on you monitor panel.

How this happens is we have black ABS plastic tanks underneath our RV which are our holding tanks, our waste water holding tanks. And we actually spin weld metal sensors into the side of those tanks and hook wires to them that go back to that monitor panel. So we use continuity of what’s in the tank. We especially see this happen on the black tanks because some slime, and some sludge, and whatever else we throw down the toilet gets caught up on those sidewalls and will actually give us that false reading.

So a couple important things I want you to do while you’re camping that will help alleviate this, or make it easier for you to clean it if the problem does arise. when you have solids or paper present in the toilet bowl, I need you to fill up that toilet bowl before you dump.

Obviously if you’re dry camping, this is going to be a little harder for you to do because you want to get as much longevity out of that tank if possible. But if we’re at a campground where we can dump whenever we like, this is a great way to do it. So if there’s solids or toilet present in there, I want to see you fill that bowl up with water. I want to get as much water as I can in that bowl before I dump.

What that’s going to do, is it’s going to do things for us. It’s going to put more water into the tank, and it’s also going to help solidify anything that we put in the tank in conjunction with our toilet chemical. Make sure you’re using the appropriate RV toilet paper.

Any toilet paper that is built for a chemical toilet will work on this. It breaks down a lot quicker than some of the household toilet papers we use for septic systems, so important to do that. So we just fill that guy up and dump it, as much water as we can. Most of your today’s toilets out there will have a way where you can step on it halfway and get some water to it, and that way we’re going to get as much into that tank as possible. If you do that that will help out.

The next thing you need to do, if it does arise, especially when you’re at the campground where you can dump where you want, we’ve got these couple of little options here that work really good. And a lot of today’s new units are coming with sewer sprays on them or some kind of tank wash spray that is hooked up to the side of the unit that actually sprays inside that tank.

Here’s a couple of options that we sell in our store. We call them swizzle sticks in the shop. Heh. You hook the garden hose to this end. It’s got a little on and off valve, and it’s actually got a sprayer that spins around at a very high rate of speed down here and will actually wash the side wall of your tank.

Here’s one that’s a little bit longer. If you own a fifth wheel, this is going to be tough to do because usually the tanks are very far away from the toilet, which are not in a travel trailer situation. So fifth wheels are a little bit tougher to do. So you can use those methods.

Another method that I use when I’m at the campground is before I leave, if my tanks are getting full, I’m going to fill that tank up with water. Now, be careful when you’re doing this because you don’t want to overfill the tank and have a mess or have it come up the toilet, but I want to fill that tank up. A lot of people I see at the dump station here at the dealership, they’ll bring a garden hose in or dump it.

You can also purchase one of these guys here. This is what my prep techs use when they are prepping a camper out to make sure everything’s working properly. They’ll drop that right in and it will keep the water on while it’s filling that tank. Again, make sure you keep an eye on that tank, because if this comes up through the toilet it’s not going to be a fun thing to clean up.

Once you’ve got that tank filled, let it sit for an hour or so. Maybe do it in the morning on the last day there, while you guys are picking up. Then go ahead and pull that valve. Now that water that’s in that tank is probably going to clean those sensors off. Sometimes I’ll even put a little chemical in there. That should clean it off, get everything taken care of for you in conjunction with one of those swizzle sticks there, and the extra water we put in. That should keep those tanks reading clean.

Now, if you have one that’s not … again, typically it’s the black but sometimes I do see it on the gray. You can fill up the gray the same way. Even put a little toilet chemical down the gray and it will help out with odors. Gray odors are just as bad as black odors. I’ve had tanks apart and they really stink. So pour a little toilet chemical down in that gray water you’re using before you dump as well. It’s not going to hurt anything, plus it will keep the sensors clean.

On the really hard to clean sensors, or if you have one now that’s been dirty for a long time and are reading full for a long time and you want to get that one done, warm water. I’ll take and fill up a five gallon bucket, and I’ll dump it down the toilet of an empty tank with, of course, the valve closed on the outside. And the steam from that warm water will actually help loosen up any solids that we might have stuck to one of those sensors inside the tank. I’ve done that on numerous occasions and had very well, great, success with that as well.

There is also product that you can purchase at an RV store that you can put. It’s called a tank sensor cleaner. I put that down in there, or toilet chemical cleaner, or toilet chemical works pretty well as well. And if it, again, it’s one of those tough ones, let it sit in there for 24 hours before you dump. Even if you’ve got to take it home and bring it to the RV dealer a day or two later after letting it sit in there. What that liquid is going to do is, it’s clean liquid, it’s going to just soften up all the material on the side of the tanks that may be giving us that false reading.

Now, on the rare occasion that doesn’t clean it out, you may need to add a new well nut or something on there. We do do that occasionally at the dealership. But those tricks that I’ve just shared with you, that gets it about 95% of the time. Hopefully, if you’ve got one of your tanks and you try my tricks, it’ll help you get that reading at empty so you can have an accurate, you know, know what’s going on in your tanks and know how full they are before you dump them. Really important with the black tank.

Once again, let it fill up as much as you can while you’re using the RV before you dump. This is going to help us evacuate the tank properly and can keep those tank sensors reading clean. And it’s also going to give the chemical enough time to break down the solids and break down the paper.

So use a lot of water if you can, if you’re not in a dry camping situation. If that doesn’t work for you and you still get a false reading, fill the tank up with water, let it sit for as long as you can before you dump. That should clear out. If it’s a real toughy, get yourself five gallons of hot water and dump it down that toilet. Let that sit around for a little while, and that’ll actually steam the sensors. And then you can go ahead and flush the tank really well. And you can try the products that I showed you earlier, the swizzle sticks and things like that.

So hopefully this helps you clean those tank sensors. Thanks again for stopping in, checking out our quick tips with Randy. And always check us out on our Facebook page, and we’d love to see you on the YouTube channel as well. Thanks for thinking of Pete’s RV and happy camping.

Pete’s RV Center is an exceptional dealership group serving the United States and Canada since 1952. With multiple locations, Pete’s RV provides sales, service, parts, accessories, and education to our community of RVers all across North America.