RV Toilet Smells When Flushed – Solved in 6 Steps

How Tos & Tips

RV Toilet Smells When Flushed

Don’t get us wrong, we think RVing is a wonderful way to travel… but it isn’t perfect. Part of the reality of living in such a small space is dealing with odors. And, let’s be completely frank: in an RV, you’re literally toting your own waste along with you for the ride. Add in a little bit of heat and time, and it’s no wonder you could be dealing with a smelly situation! RVs aren’t very big spaces. For this reason, when a stinky smell is present, it makes itself known all throughout the tiny home in no time at all.

Unfortunately, there are several different things that can cause a stink in a motorhome or travel trailer. Full trash cans, dirty dishes, and even a full gray tank can all create unpleasant odors that waft through the rooms of your home-on-wheels. Perhaps the most offensive of all, however, is when your camper smells like sewage—a smell that almost always comes from the RV toilet.

RV toilet odor can have a few different causes. Fortunately, the majority of these issues are relatively easy to deal with, meaning you can get rid of the smell fairly quickly and without much headache.

In this article we will discuss the most common reasons a camper toilet stinks and how to address them.

5 Reasons Why Your RV Toilet Smells

The first thing you’ll need to know is the reason why your camper toilet smells bad. After all, you can’t very well fix a problem without knowing exactly what the cause is. Below are the 5 most common reasons an RV toilet smells when flushed.

Dirty Toilet

The first problem is also the easiest to fix. Sometimes, RV toilets—especially those of the plastic variety—will hold onto smells. The longer you wait to clean the toilet, the more stink it’ll hold onto, until eventually the smell fills the entire RV.

Fortunately, this is super easy to fix. A simple cleaning with your favorite household bathroom cleaner should get rid of the smell in no time. Just be sure you get every nook and cranny.

Clogged Black Tank

A clogged black tank is another common problem, and this one is not quite so easy to deal with. If you have a clogged tank, it won’t dump completely—or at all, sometimes—meaning you’re left with old sewage hanging out in your tank for days, weeks, or even months on end. Obviously, this isn’t going to start smelling any better anytime soon. Therefore, you’re going to have to address the clog.

Usually, a clog is caused by too much toilet paper and not enough water. Sometimes this means you aren’t flushing long enough; other times it’s because the dump valve was left open, allowing all liquids to leave the tank and leaving just the solids behind. A leaky black tank can also cause this same issue. Of course, it could also be caused by something being flushed that should not have been.

In any case, there are a number of methods for getting rid of such clogs:

  • Some people will dump a bag of ice down the toilet and drive the RV around, allowing the ice to break up the clog.
  • Others use special black tank chemicals to attempt to break up the clog.
  • We’ve even heard of people using boiling water.

Our favorite method, however, is to backflush the tank using a gadget such as this. Just make sure your tank isn’t full already, as spraying more water into a full tank may cause it to back up into the toilet and your RV bathroom.

Need to know more about unclogging your black tank? Check out our article on the subject.

Clogged Vent Pipe

Sometimes the problem isn’t a clog in your tank, but rather a clog in the vent pipe.

You see, every RV has a pipe from the black tank to the roof, allowing methane gases to escape. If this vent becomes clogged, those gases can’t escape through the roof, and will instead come up out of the toilet when you flush. As you might imagine, this does not smell good.

To check a vent pipe for clogs and get rid of anything that could be obstructing the airflow, simply put a garden hose into the top of the pipe and run some water through it.

Tank Buildup

Occasionally an RV toilet stinks because of buildup in the black tank. This might be a large buildup of solids on the bottom of the tank, or just buildup along the walls of the tank from regular use.

As with clogs, solid buildups tend to be caused by too many solids and not enough liquid in the tank. This can be avoided by keeping your dump valve closed, ensuring your tank doesn’t leak, and using plenty of water when flushing.

A solid buildup can be gotten rid of using the same methods you might use to get rid of a clog. Once again, we highly recommend backflushing.

Unfortunately, general buildup on the walls and bottom of the tank cannot be avoided. Instead, walls must be cleaned regularly in order to avoid a stink. You can clean these walls by flushing the tank and using tank cleaning agents such as Aqua-Kem.

Bad Toilet Flange or Bowl Seal

The last possibility is that your toilet needs a new flange or bowl seal. Both of these seals have a tendency to become worn over time, something that can cause bad camper toilet smells.

If you notice that your toilet bowl won’t hold water, it’s likely that you have a bad seal that is also allowing stinky black tanks smells into the RV. Meanwhile, a leak around the bottom of the toilet would indicate a worn gasket that could be letting smells in.

How to Keep Your RV Toilet from Smelling

Clearly, you won’t want those smells to return once you get rid of them. Fortunately, it’s easy enough to avoid RV toilet smells. If you’re wondering how to keep your RV toilet from smelling, just keep up with your toilet and tank maintenance and you’ll be golden.

RV Air Freshener

First of all, there are a few simple steps you can follow in the bathroom that can really help eliminate RV toilet odor.

For instance, pay attention to your camper roof vents. Although they’re great at eliminating odors in general, it’s a good idea to close the rooftop vent when you’re actually flushing the toilet. Think about it: you’re opening up the valve and exposing the tank below, and the vent will pull all those fumes straight up and into your RV’s atmosphere like a vacuum!

Also, be sure to use an appropriate amount of water when you’re flushing your RV’s toilet, as water helps activate any odor eliminator chemicals and also naturally helps to block waste odors on its own.

Another thing that can really help minimize RV toilet tank odors is simply keeping the tanks as clean as possible between dumps. This can also help regulate your RV’s holding tank sensors, so you’ll be able to tell for sure how full your tanks are — here’s an article we wrote on how to keep them nice and clean.

But when it comes to the heavy lifting of RV odor elimination, you’re going to have to add some extra items to the tank itself.

Best Odor Eliminator for RV

With so many RV holding tank treatments to choose from, which is the best? When staring down all the options in the store aisle, it can be difficult to know which RV odor eliminator kit will take care of the job most efficiently.

Commercial RV odor eliminators come in lots of different styles and types, from gels and liquids to powders. No matter which kind or brand you choose, the idea behind why they work is similar: The chemicals, when combined with water, not only help combat unpleasant smells but also help to break down solid waste and toilet tissue, which makes flushing your rig’s tank much easier.

Happy Campers offers an all natural and organic cleaning and deodorizing product that is easy to use and just plain works. We like their product because it’s a natural formula that is Environmentally friendly, 100% Biodegradable, 100% Organic, and with no formaldehyde.

RV Odor Eliminator Ingredients

That’s right: you can make your own, homemade RV tank deodorizer. In fact, it’s pretty darn simple to do!

There are many different recipes available online for homemade RV odor eliminators. All of them are designed with the same purpose in mind: to combat odors and also to help break down solid waste to keep your RV’s holding tank and pipes in good, working order.

Many campers like making their own toilet tank odor eliminators because it’s more natural and they have complete control over the ingredients. (This is especially relevant if you have small children on board, who might think those brightly-colored commercial chemicals look good to drink — not good!)

For others, the decision to concoct their own odor eliminating potion is a simple one: It’s cheaper! But either way, you’ll have to experiment with different ingredients and recipes and figure out which one works best for you.

Here are a few DIY RV odor eliminator ideas from campers around the web:

You’ll notice that all of these homemade concoctions generally call for the same basic components — some sort of mild soap, which cleans the tank and keeps down odor, and a water softener, which helps liquefy solids.

Play around with a few different versions, or maybe even come up with your own! 

RV Toilet Smell Prevention and Maintenance Tips

Not sure what toilet and black tank maintenance looks like? Using the tips below will help make sure you never have to deal with a stinky RV toilet again:

  • Keep the black tank closed.
  • Use plenty of water when flushing.
  • Add chemicals to your tank after every dump.
  • Flush out the black tank after every dump.
  • Keep your toilet clean.
  • Check the vent pipe regularly.

Final Thoughts

Now that you know how to take care of those pesky odors in your rig, you can sit back and enjoy the fresh scent of a well-cared-for camper.

Want to know more on the care and keeping of your RV black tank? We recommend checking out this article to cover your bases and ensure you know all there is to know.

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