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How to Unclog an RV Toilet: Tips to Keep the 💩Flowing!

How to Unclog an RV Toilet: Tips to Keep the 💩Flowing!

If you’ve ever had a clogged RV toilet, you know that the best way to tend to it is to prevent clogging in the first place!  But, with that obvious statement aside, we all know that solid waste and paper can sometimes create a clog. For this reason, it’s a good idea to know in advance how to unclog an RV toilet before it happens.

That’s the purpose of today’s post…preparation!

So, whether you’re faced in the future with a pyramid plug like this —>💩 causing a problem in your toilet bowl, black tank, or sewer line, we’re going to arm you with the knowledge to conquer the 💩!

Glove up and let’s go!

Where Do RV Toilets Clog?

RV toilets are most likely to occur in one of four locations.

Blade Valve

Some clogs occur right at the blade valve located at the bottom of the toilet bowl. The cause of this is generally either too much “stuff” (solid waste and toilet paper) sitting in the bowl itself, or too little water in the bowl before that “stuff” was added.

Transfer Pipe

An RV toilet may also be clogged in the pipe or tube that leads the toilet contents from the toilet down into the black tank. The cause of a clog in this location is likely similar to a clog at the blade valve – too much “stuff” and/or too little water!

Black Tank Inlet

A clog may be located at the outlet/inlet to the black tank itself. In other words, just before the waste and paper exit the pipe/tube and drop into the black tank.

Black Tank

A clogged RV toilet can also be caused by a backed-up black tank. If your black tank overflows, you’ll have a clogged toilet because the waste won’t be able to descend into the (full) black tank.

An overflowing black tank is generally caused by either not dumping your black tank in time or not dumping it completely.

If you’re relying on your RV holding tank sensors to tell you when to empty your black tank, you’ll want to make sure that they’re working properly.

Now, tank sensors are notorious for delivering false information. But one thing you can do to help is to clean your RV tank sensors

And no matter how meticulous you are about keeping your RV sensors clean, if you’ve been using your RV for years, you’ve very likely got a build-up of struvite (which can prevent tank sensors from reading correctly), requiring a power-washing of your black and gray tanks. 

What Causes RV Toilet Clogs?

The answer to this question depends to some degree on the location of the clog. But there are a number of things that can lead to an RV toilet clog.

Too Much “Stuff”

As we noted above, excessive “stuff” in the bowl can cause a clog at the blade valve (where the toilet opens to drop the contents below).

The same thing can occur (for the same reason) when you flush the toilet and too much “stuff” enters the pipe/tube that leads to the black tank. The waste & paper can get stuck in that tube, unable to drop into the black tank.

Tank Build-Up

An RV toilet clog can also occur when waste and paper build up inside the tank itself. When this occurs, (and it’s very common), it’s generally because the waste and toilet paper aren’t able to break down sufficiently in the tank.

In fact, if you’re not using any product to help break down waste, this is a likely culprit of your RV toilet clog.

Excessive Heat or Cold

When the weather is excessively hot or cold, waste products tend to become more solid as they sit in the holding tank below the RV.

This can lead to RV toilet clogs when waste piles up inside the tank and contents back up into the toilet.

Hot weather can be especially problematic because liquids in your black tank that are necessary for keeping things “moving” well are more likely to evaporate, leaving solids stuck in the tank.

Cleaning toilet bowl with water sprayer

Plenty of liquid in the black water tank is necessary to keep solids from drying out. Hot weather can evaporate liquids, causing solids to dry up and stick to the tank.

Remember – liquids in the tank are necessary to keep things moving along! If solids get stuck in the tank and don’t move through when you empty your tanks at a dump station, then those solids are left behind. As you continue to use your RV toilet, the solids in the tank aren’t breaking down and are taking up space in the tank, and will eventually lead to a clogged toilet that is very unpleasant to deal with!

This is why you NEVER leave your black tank dump valve open when you’re connected to sewer at a full hook-up campsite. Doing so will result in all the liquids draining out with each flush, but leaving the solids behind to pile up (commonly called “pyramiding” due to the shape of the resulting pile. 😝)

How to Unclog an RV Toilet

Now that we have a better understanding of how RV toilets can get clogged and where those clogs can occur, let’s take a look at how to unclog an RV toilet… and, once you do unclog your toilet, how to prevent it from happening again.

Hot Water

If you’ve got a clog above the tank (either at the blade valve, in the pipe/tube leading out of the toilet, or at the end of that pipe that is the entrance to the black tank), pouring some hot water into the bowl and flushing the toilet may be all that’s needed to clear the clog. 

Many people use boiling water for this purpose, but be careful with boiling water in an RV toilet. Not only can you burn yourself with boiling water, but it’s possible that it could damage seals and cause other issues. Very hot (but not boiling) water is often sufficient to clear a clog.

Dish Soap

Pouring some dish soap into the toilet bowl and flushing may also be helpful to move the clog through the system and into the black tank. 

Photo of a person pouring a liquid (Rid-X) into a toilet bowl

Liquid dish soap can help to dislodge a toilet clog.

You don’t need an entire bottle – maybe about a cup or so. 

If your clog is beyond the blade valve inside the pipe leading to the tank, simply add the dish soap to the toilet bowl and flush it into the pipe and let it work for a while to unseat the clog.

Toilet Wand/Snake

Before we discuss this method, we want to note that if you have a macerating toilet, this is NOT an option for you. A macerating toilet is different and may call for appropriate chemicals to break down stubborn clogs. We suggest reading your macerator owner’s manual for your best options.

For regular RV toilets, however, an RV toilet wand can be a very helpful tool to have on board.

While you wouldn’t want to use a toilet snake designed for home toilets, there are toilet wands that are very useful for clearing tough clogs and cleaning out a black water tank once it’s been emptied.

Remember that most RV black tanks are positioned directly beneath the toilet, so a traditional toilet snake is really too long for an RV toilet setup.

PRO TIP:
When you have a difficult clog that has to do with an overflowing black tank,  your very first course of action is to dump your black water tank.

Thereafter, one of the following toilet wands works very well by using water to clear clogs and clean the system. 

The first option has over 10,000 positive Amazon reviews for good reason. The second option is a bit less costly.

Sale
Camco RV Flexible Swivel Stik with Shutoff Valve - Creates Powerful Cleaning Action that Dislodges and Flushes Stubborn Waste Deposits and Combats Odors (40074), 55-1/2 Inch
  • Powerful rotary cleaning action dislodges and flushes the stubborn waste deposits and odor-causing particles left after holding tank is emptied
  • Solid section including handle measures 24" long; the flexible section measures 34" long with a 2" diameter nozzle

Black Tank Cleaner

Black tank cleaners help to break down and dissolve the contents of the black tank, effectively eliminating clogs.

Perhaps the best thing about a high-quality black tank cleaner, however, is the fact that it can also PREVENT clogs from developing in the first place.

We use and highly recommend Happy Camper’s. Its septic safe mineral blend is activated by water and not only breaks down waste but also eliminates odor.

Happy Campers RV Holding Tank Treatment - 64 treatments
  • ODOR FREE: Eliminates odors in the RV holding tank. Absolutely no chemical or sewer smell.
  • Septic tank friendly

By the way, your RV toilet really shouldn’t have an odor. So, check out our post on the topic if your RV toilet stinks!

Ice Cubes

And, finally, some RVers swear that ice cubes deposited into the black tank are an inexpensive way to possibly get rid of clogs and solid waste build-up. ($3 for a bag of ice at any McDonald’s)

Pouring ice cubes into an RV toilet

Pouring ice cubes into the black tank and driving around for a while can help to dislodge solids in the tank.

The idea is to toss the ice cubes into the black tank (through the toilet), and then go for a drive. As you round curves and drive over bumps, the ice cubes are thought to dislodge waste and toilet paper that has dried and caked onto the sides and bottom of the tank.

Be aware, though, that this won’t help if you’ve accumulated a large enough 💩 pyramid because you left your black tank valve open at a full hook-up campsite. It’s really more a technique for helping to remove built-up residue in your tank that may be causing a bad odor.

Should I Use Special RV Toilet Paper to Avoid Clogs?

No. We don’t recommend wasting your money on “special” RV toilet paper. We’ve got an entire post on the topic of RV toilet paper and we encourage you to read it before spending your hard-earned money on “RV toilet paper”.

If you’re interested in learning how to test for RV-safe toilet paper, feel free to check out our YouTube video on the topic:

Tell Us About Your Experiences Unclogging An RV Toilet!

Have you ever had to figure out how to unclog an RV toilet on your own? Or have you ever used any of the techniques we’ve listed above? If so, drop us a note below in the comments and share your experience!

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Revbucco

Sunday 16th of October 2022

We lived for over 15 years in Latin America. Our first introduction was being told ‘don’t flush the toilet paper!’ Turns out they use smaller diameter drainage pipe and any paper in the pot will cause stoppage. All paper had to be thrown into a trash container in the bathroom with a lid and disposed with the trash.

When we owed our first 5th wheel we had a huge problem with our black tank and it took hours to finally clean out the black tank and get things flowing again. We decided to revert to our Latin America experience. Saves money as we don’t have to purchase RV toilet paper and we can go longer between flushing our tanks. We reuse the plastic garbage bags you get at the grocery park store and take it with us each day when we head out and throw them in the campground dumpster. We also save money on not having to purchase additives to literally throw down the drain to aid in decomposition.

Best decision we have ever made.

Dennis Johnson

Saturday 15th of October 2022

Always, before going #2, add a few inches of water to the bowl. Saves a lot of grief and helps with "cling-ons".

TheRVgeeks

Saturday 15th of October 2022

Now that there is what ya call good RVing advice. Thanks Dennis!

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PLEASE NOTE: We're handy RVers, not professional technicians. We're happy with the techniques and products we use, but be sure to confirm that all methods and materials you use are compatible with your equipment and abilities. Regardless of what we recommend, consult a professional if you're unsure about working on your RV. Any task you perform or product you purchase based on any information we provide is strictly at your own risk.

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