Show
RV Black Water Tank Clogged? Here Are Easy Ways To Unclog It!By Kelly Beasley Published: October 5, 2021 Last Updated: August 14, 2022 A toilet back up in your camper is probably one of the most unpleasant aspects of RVing! It doesn't have to happen, and it's preventable. But if you're reading this, I'm guessing you already have a clogged black tank, my friend! Bummer for you. The good news is that all waste clogs are fixable. (As long as there are only four things in your dump tank: water, urine, TP, and bowel movements!) It would be best if you put down no other solids or other waste types into your RV black tank. Don't worry. In this guide on unclogging an RV black tank, you'll learn all you need to know to diagnose, remedy, and best of all, FIX your clogged RV toilet. Read on to learn how to unclog an RV black water tank. Types Of RV Toilet ClogsThe things that clog an RV toilet are any combination of these three things: toilet paper, solid waste, and hardened solid waste. That said, there are three ways an RV toilet can clog: Pipe ClogYour RV toilet's drain pipe leads from the toilet's base and moves all waste down into the black tank. Sometimes it's a vertical pipe, and other times, there are bends in the waste pipe as it heads down into the black tank. Most often, a pipe clog happens in the type of RV toilet setup that has twists and turns in the pipe. If the black tank is not directly under the toilet, bent elbows (turns in the pipe) are required to get the sewage into the black tank. This is where the problems usually occur. Typical mistakes that clog a pipe are:
Poop PyramidThis one is just as it sounds. It's a pyramid-shaped pile of your poo down in the black tank. This is always caused by a novice RV owner leaving the valve to your black tank open while parked and connected to a dump (most likely when you are at an RV site with full-hookups). Keeping the black tank valve open when connected to a dump allows the liquids to escape out of the black tank. Meanwhile, the solids remain where the land when coming out of the pipe from the RV toilet. (The solids you flush down the toilet require a certain amount of liquids in the tank in order to be removed/drained.) There's your poop pyramid. Eventually, the pyramid grows so tall it touches the toilet pipe until finally, your toilet can't drain into your tanks. Compacted Tank Or Hardened SolidsIt's not super likely, but it's possible that if you don't use enough liquids, a mass of solid matter could accumulate at the bottom of your RV toilet holding tank. Similarly, if you store your RV for long enough with contents still in the RV's black tank, the liquids will eventually evaporate out. This practice leaves the solids in there, and eventually, at worst, they will dry and harden. (Remember, there's a vent in your blackwater RV holding tank. So, it's not sealed tight.) So My Black Water Tank Clogged. Now What?The next step is to determine which type of clogged black water tank you have. (Pipe, pyramid, or compacted.) Whichever type of clogged black tank problem you have determines what steps will unclog the blockage. Three signs that hint at what is going on:
It's an excellent idea to have a clear RV sewer hose adapter so you can see how much is or is not draining from your black holding tank. How to figure out what these clues mean:
How Do You Unblock An RV Black Tank?The method you'll need to utilize to unblock your black water holding tank 100% depends on what type of blockage you found. Here we share with you the fix for each. How To Unblock A Poop PyramidTo unblock pyramid plugs, first, you must diagnose that it is indeed a poop pyramid causing your tank clog. Three things determine a pyramid is clogging your toilet:
If these three match up with your situation, congratulations! You have a poop pyramid. Here's how to unclog an RV with a poop pyramid.You can try a few methods. Your main goal is to open up a channel where you can get water into the tank to fill it up. Here's what you should do first:
How To Unblock A Compacted Black TankTo unblock a compacted tank, first you must confirm that indeed it's a compacted RV holding tank. Here's what determines that you have a compacted tank:
So now you know how to unclog an RV black tank. Be aware that this type of clog might take a little more to eliminate (no pun intended). This is especially true if you stored the RV without dumping your blackwater tank. The solids are now hardened at the bottom of the tank. You might need 2-3 times to get it completely clear. Here's how to unclog an RV with a compacted blackwater tank:
Liquid Tank UncloggerAll three of the ways to unplug an RV holding tank call for some sort of liquid enzyme treatment to assist with the process. You may want to try the Unique brand tank cleaner as it's specifically formulated to deal with clogged pipes, poop pyramids, and a compacted tank. How To Clear An RV Toilet Clogged PipeThis type of RV toilet tank clog might act like having a poop pyramid. However, if you DID NOT leave your blackwater tank open while connected to a sewer, and you DO NOT have a black RV tank leak anywhere, a toilet that won't drain out the sewer line means a clogged pipe. Here's how to unclog an RV with a clogged toilet pipe.
How To Maintain A Healthy Black TankCongratulations! Now it's time to figure out why you had a clogged black tank pipe and learn what it takes to prevent future clogs. Here are the conventional ways to avoid a clogged toilet:
DEMONS!!!! LOL
The best way to prevent a blackwater tank clog is this: Do NOT put your toilet paper down the toilet. Instead, put it into a wastebasket. It sounds gross, but it's not AT ALL. I (Kelly) have not been dumping TP down my toilet's plumbing for about 5 years, and I have never had a clog. Better yet, I can use any brand of TP I want! Finally, it saves tank space when you're boondocking, so that you can stay out longer before having to dump. OK, enough preaching. Hopefully, you'll use septic-safe TP and more water than before, and you'll never have any future clogs in EITHER of your tanks. Now that you know, you can prevent one from happening easily with this regular maintenance of your black tank. Regardless, I hope you never have to deal with your human waste in this fashion again! How To Unclog A RV Toilet Holding Tank- MYTHS!I am including methods I've seen others claim work by doing a Google search. Some of them are downright ridiculous. But here we go: Ice MethodThis simply doesn't work to dislodge anything from your black water tank. If you tried it and it worked, it was sheer luck. If you have a clogged pipe, water and ice aren't going to be able to get up there to dislodge it. If you have a poop pyramid, the only 'rubbing' the ice will do is very minimal and only in ONE level of the clog. If you have a compacted tank, well, floating ice won't even touch the stubborn waste. Boiling WaterOK, help me out with this hot water method. HOW is hot water or boiling water or even warm water going to break anything up? It doesn't have the ability to eat/remove anything. I can't believe I even read this as a 'solution' on another website. Hot water? Please. Good for grease clogs? Maybe. Good for poop clogs? Nope! (Unless you eat a lot of grease maybe? 😉 ) Vinegar and Baking SodaAgain. Please. Maybe try pouring this onto some dog poo and see what it does. It will be a whole lot of nothing. Don't waste your time. If you think some tiny bubbles are going to move sh**, you're wasting your time. Besides, the reaction that causes the bubbles lasts for a very short time. No, this one is not going to work. (Though it's a great way to make a volcano!) Dish SoapAgain, how is liquid soap going to work? If poo and TP are stuck to a wall or in a pipe, nothing will get the soapy water in between the stuck object and the wall or pipe. This fixing method for tanks just isn't a viable option though there are people out there who claim it worked for their camper toilets. It MIGHT help out a gray water tank to help degrease and do a little tank maintenance, at best. If their solid waste caused black tank clogs, it needs to be EATEN/LIQUEFIED by something or physically moved by an object such as PEX pipe. Harsh ChemicalsYou might be tempted to use some harsh chemicals in your holding tanks to clear out waste. Again- why? You risk damaging the seals in the plumbing that keep leaks at bay. Besides, it's best to keep these chemicals out of the dump station or septic tank you're using. Pressure WashingUsing a pressure washer MIGHT work. However, it's much less messy and easier to use some kind of drain snake to puncture through pyramid plugs or RV clogs. Some claim you may accidentally puncture through your clogged blackwater tank using a pressure sprayer into the toilet, but I don't believe that one. If your black tank needs a serious cleaning, there are professionals who will pressure wash your holding tanks. This is probably your best option when it comes to pressure washing. Black Tank FlushA black water tank flush MIGHT work, but only the wand type flusher. And only because you have to puncture a hole through the tank's contents if you have a pyramid or a clog, so it could push a blockage through or at least open a hole so you can get drain unclogger product down the tank. That said if you try to use a backflush method where water is sprayed into the tank through its exit plumbing (your RV's drain pipe you use to dump the tanks), good luck. This won't work. If you've seen what the inside of a tank looks like when one of these pretty worthless flushes was happening, you'd understand why. Why Does My Black Tank Keep Clogging?Your black tank keeps clogging for one of a few reasons.
How Do You Snake An RV Black Tank?To snake an RV black tank, get yourself some PEX pipe. It's flexible so if you have bends in your waste pipe, it will still work. Plunge through your blockage until you can get water into your tank. Fill it and then use an enzyme treatment to dissolve the plug. What Do You Do If Your Black Water Tank Won't Drain?If your black water tank won't drain or flush out, don't panic. You have an obstruction that needs clearing. Figure out what type of blockage you have first, then follow our directions above to clear out that blockage. ConclusionZero RV owners want their RV black tank clogged. It's bad enough you have to deal with your RV dump hose and your human waste in your travel trailer, 5th wheel, or motorhome. But worse, having your RV's toilet not working right can cause your camping trip to go very, very wrong. It's a gross and smelly job to fix. If your black water tank will not drain its waste water, there are three types of clogs you potentially have. A poop pyramid, a pipe clog, or a compacted tank. Fixing them shouldn't be too hard. Simply figure out which one you have, and then follow the above directions for the type of clog you have, and you are good to go. Here's hoping this is the last time you have clogging to deal with, as this is a common issue. A blockage only happens to those who don't know how to prevent them! Now you know how to avoid future clogs. Hello! I'm the co-founder of Camp Addict, which my biz partner and I launched in 2017. I frigging love the RVing lifestyle but in December of 2020, we both converted to part-time RV life. Heck, I lived in my travel trailer for over 5.5 years, STRICTLY boondocking. I learned a lot about the RV life and lifestyle during those years. Now we share what we know with you here at Camp Addict. After that many years of wonderful full-time travel, it was time for something new. These days, I'm often found working from my new Az home, and sometimes plotting and scheming whether or not to start collecting farm animals (or plotting my next RV trip!). Other Articles You Should Read |