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RV Nightmare: How to Unclog RV Toilet or Tank

RV Nightmare: How to Unclog RV Toilet or Tank

A clogged RV toilet might be one of the worst things that can happen to you on the road. Having a toilet on the go is an amazing feature of RV’s, but they can be susceptible to problems. If your experiencing this or just want to know what to do when and if it happens read on.

Oh No! My RV Toilet Is Clogged

This little-talked-about problem is actually quite common. But if not taken care of, it could cause some major headaches—the worst being water damage from overfilling. What typically happens is the toilet paper and body waste don’t get fully flushed and end up sticking to the pipes or tank. Over time, it dries, gets hard, and more things get stuck until nothing can get through.

In addition you might find that you have the valves open to dump but nothing is coming out! So, what do you do to unclog your RV toilet?

toilet paper in toilet

How to Unclog Your RV Toilet

If you find your RV toilet is not flusing or you cannot dump your tanks, then you have a blockage. At this point you need to try and break it up. Lets take a look at a few methods to do this, from the easiest to mode invasive.

The Boiling Water Method to Unclog RV Toilet

First, try boiling water and pouring it down the toilet. This is in hopes that the hot water will loosen everything up and unclog the RV toilet. However, it might take a few times to really clear the clog up. So, don’t give up if the first try didn’t work.

This usually only works when the toilet pipe itself is clogged. If you tank wont empty move on to another option.

Pressurized Water

This can work very well or be a huge mess. If your toilet is not flushing at all then this might not work. If its slow then you might have a chance. Hook up a hose and run it through a window inside the RV to the toilet. Use a sprayer nozzle to spray a high flow of water down into the tank. If you have a pile of debris built up its likely that it will break it up. Make sure the tank drain is open at this point.

If your tank is not draining you can get a simple hydroflush attachment that connects a hose to the outlet. Turn the hose on and open the tank. It should jet water up into the clog and possibly break it up. You may need to turn the water on and off a few times.

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We personally use this technique to get a good clean on our tanks every so often while dumping.

Using a Plunger or Toilet Snake

The next option is to use a plunger or toilet snake. A plunger might not be the most effective if there isn’t an airtight seal. So if that doesn’t work, use a toilet snake. Make sure you get one long enough and sturdy enough to really grind up anything in the pipes. 

Unclogging an RV toilet with a plunger or toilet snake is best done by someone who isn’t completely grossed out by the toilet as it might be a mess.

Insert the snake into the toilet or drain pipe and push back and forth and spin it. It will loosen and break up debris and allow it to flow. If you are trying to dump the tank you could end up spilling sewage when it breaks up so have a bucket under the pipe.

RV toilet

Unclogging Your Toilet with Holding Tank Cleaner

You could also try holding tank cleaner. Because black tank cleaner breaks down human waste, it could help break down the clog. The issue with this option is it won’t eliminate the clog, and it could take a few hours to take effect.

To use it, add the cleaner to the tank along with a few gallons of water if it will go down, and then take the RV for a drive. Make plenty of turns to slosh it around and help it break everything up. Then try flushing out the tanks and running the toilet.

Tips for Preventing RV Toilet Clogs in the Future

The best way to avoid a clogged RV toilet is to take preventative measures. There are a few things you can do to help limit clogs in the future. 

Keep Black Tank Closed Until Ready to Dump

The best prevention is not leaving your black tank valve open except when dumping. If you leave the valve open when using the toilet it allows solids to build up in the tank without enough water to soften the “Stuff” up. When you attempt to dump this dried-out mass can clog up the tank output. When stuff gets left behind, it dries and becomes harder to get rid of. Then over time, this builds up, creating the dreaded “poop mountain.” This is a pile that builds up directly below the toilet.

Easiest solution, let the tank fill until its time to dump. You can dump the tank at any point but the more liquid in the tank the better the flush will be.

dumping rv sewer at dumpstation

Only Use RV Toilet Paper – Or Put Paper in the Trash Instead

Never flush anything other than RV toilet paper down your toilet. Flushing regular residential toilet paper or feminine products is sure to cause issues. The best thing you can do is throw toilet paper in the trash. But if that’s not something you can stomach, only use RV toilet paper. It’s made to dissolve easier, so you’ll have to unclog your RV toilet less.

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Use Plenty of Water With Each Flush

The other thing people don’t do enough of is use lots of water when flushing. This will ensure that anything going down the pipe doesn’t get stuck there and passes to the black tank. Too often, people don’t use enough water. 

You could also eliminate RV toilet clogs altogether by investing in a waterless toilet. Composting toilets and incinerator toilets are two good options!

Use RV Waste Tank Treatments

Another preventative measure is to use black tank treatments regularly. The black tank treatment breaks down human waste. This will help prevent any clogs and build-ups. It also helps prevent any bad smells as well. 

We recommend using Happy Campers Holding Tank Treatment

How To Dump & Clean an RV Black Tank

Clean Your Black Tank Each Time You Dump

Lastly, clean your black tank every time you dump, making sure you flush water through the system from your toilet. Many RVs come with a built-in black tank flush inlet that allows you to connect a hose directly and rinse out your black water tank without having to run water through your toilet. 

If your RV does not have a black tank flush or it does not work you can run water through the toilet or even run a hose into the RV and fill the tank through the toilet.

Or, you could buy products that help shoot high-pressure water up your blank tank to give it a good rinse.

Never Store an RV With A Dry Black Tank

Unless you are sure that an RV black tank is super clean never store is empty. Any solids left in the tank will dry up and can contribute to a clog in the future. The best way to store an RV black tank is partially full of black tank chemicals in the water. This will make sure any solids dissolve in the time stored. If storing in freezing temperatures also be sure the tank has antifreeze in the water and that the tank is not more than half full.

Doing this will make sure your black tank is ready to go come camping season!

If Your RV Toilet Clogs, You’ll Be Ready!

We hope that our tips today help you prevent it, but now you know how to unclog your RV toilet in the worst-case scenario. If it does happen, don’t be ashamed. This is a common problem almost everyone encounters at some point. It’s not a big deal, but you want to make sure to take care of it before it becomes an issue.

RV bathroom with toilet

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Tom & Caitlin Morton of Mortons on the Move gave up the stationary life for one where they are constantly on the move. They are full-time travelers, television hosts, and digital media producers.
They left their jobs, sold their house and possessions, and hit the road in September 2015 in their full-time “home on wheels”. Since then they have traveled the US, Canada, and even internationally by RV.
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Sunday 30th of January 2022

Hi! I’m curious about your toilet? Is it a household toilet? There would be nothing to plunge in mine because it is a straight shot to the black tank. Thanks! We were just discussing if you should ever use a plunger on an RV toilet and came across your article.

Mortons on the Move

Tuesday 8th of March 2022

So in some RV's its not a straight shot, but most are. It is possible if somone leaves the black tank open to get a pile buildup that blocks the pipe. We have macerator toilets that can get clogged as well.

Cyrus Juliet

Tuesday 7th of September 2021

To unclog an RV toilet, simply use boiling water. However, ensure that the pieces of your toilet are strong enough to withstand the high temperatures.

Roof Leaks

Monday 22nd of February 2021

A clogged RV toilet can lead to a nasty smell that can permeate the interior of the vehicle and make your trip unbearable. If you find yourself in such a predicament, then there are different ways as you have already mentioned which can unclog your RV’s toilet holding tank.


Sunday 7th of February 2021

The most important piece of advice is using lots of water. But you forgot one thing. When storing your RV make sure you have water And treatment in the black tank. Don’t store with the black tank dry, unless you are absolutely sure it is clean.


Monday 8th of February 2021

I literally just read an entire paragraph or two about halfway into the article or whatever u wanna call it that went over this extensively lol. They didn't forget.

Mortons on the Move

Sunday 7th of February 2021

Great point!

Robert Mosier

Sunday 7th of February 2021

I put a bidet on my toilet, it replaces the toilet seat . It is simple to install, only takes 30 minutes if you take your time. Saves a ton of toilet paper, you only need a few sheets to pat the water drops off your hind end and if you want to just throw your tp into the trash all it is is damp. I have them on all our toilets. I also replaced my RV toilet with a porcelain one from Thedford, stronger and taller. The nicer bidets that just replace the toilet lids cost around $200, the one in my RV cost less than $80. Safe travels, Bob

Mortons on the Move

Sunday 7th of February 2021

Thanks for your comment Bob! We have heard of people doing this with RV toilets but good to hear first hand experience :)

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