How do I unclog my RV’s toilet?

That’s a messy situation, to say the least, and the one service call we dread (though will cheerfully respond to and do our best!). Right off the bat, we’ll tell you it’s difficult to clear a clogged toilet without the right type of professional equipment. But there are a couple of things you can try.

Most RV toilets either have a drop-down pipe straight into the black tank (the best situation) or they have a pipe that takes a bend and may travel a bit under your RV to finally get to the black tank (NOT the best situation for a clog). That bend means that your RV’s toilet will likely get clogged up more often unless you take some extra precautions (more about that later).

We will say that most clogs are toilet paper (and not human waste) in the pipe from the toilet to the black tank. The buildup in TP comes from not using enough water and/or using too much TP at once.

Some RV owners will use an RV toilet cleaning wand, a long (24″ to 30″) tube of plastic that connects to a garden hose and has holes in the end to spray water down the toilet, into any sort of piping, and then into the holding tank. There’s a version of this tool available that has about 24″ to 30″ of flexible hose at the end which can help too.

While this may work in some cases, many RV toilets have that bend in the waste pipe or longer drop into the tank. Plus, using these flush wands could introduce human waste into the interior of your RV. Yuck!

You might also try dumping a couple of gallons of very hot water into your toilet. Some RVers have had some success with this method. We would advise you to open your black tank’s release pull while trying this method.

The last option would be to use the Valterra Flush King Back Flush Valve. It’s a specially designed contraption that you attach between your RV’s pipe (that normally connects to the flexible sewer hose) and the flexible sewer hose itself. The valve allows you to force water back up into your black tank and can clear clogs that may be in there. For more information on the Valterra Flush King Back Flush Valve, please read this article.

If none of that works, your next move would be to call a professional RV tank cleaning service like Kleen Tank. We have special equipment to clear mounds, clogs, and other obstructions. You may want to contact us for this special situation — a complete tank cleaning is also part of our process to clear the problem.

As always, we recommend that you use plenty of water when you are using the toilet. Starting with a half bowlful of water is a must, then you “do your business,” flush that down, fill the bowl halfway again, flush that, and finally fill the bowl halfway for the next use.

Jim & Debbie Tome, Owners

Hi, we're Jim and Debbie Tome and we're the owners of Kleen Tank LLC, the nationally-recognized and largest professional network of RV tank cleaning service provider.

We've been RVers like you since 2004 and have traveled all over the U.S. in our Airstream travel trailer. We started the business about twelve years ago and have cleaned tens of thousands holding tanks in thousands of RVs. From tiny weekend travel trailers to monstrous fifth wheels to luxurious motorhomes, we've seen just about every situation there is with RV holding tanks and waste systems.

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