how does an RV toilet work
Last Updated: May 18, 2021

How Does An RV Toilet Work? (Flushing, Composting, And Portable)

Curious about the works of an RV toilet? The classic RV toilet is not that different from your household one, except for the flushing pedal. But that’s just one of several different types of toilets that can be installed in RVs, and that’s exactly what I will be talking about in this guide!

From the basic differences between household and RV toilets to the intricate process of dumping your RV waste tank – this guide covers everything you need to know about RV toilets and how they work!

Household Vs. RV Toilet

Household Toilet

Although the exact way a toilet works depends on the type of toilet, there are a few things that all RV toilets have in common and that makes them different from household toilets.

The first one is design – household toilets are usually quite heavy as they are made from porcelain. RV toilets, on the other hand, are much smaller and lighter. There are some ceramic RV toilets you can put in your vehicle, but most people go with either plastic or wooden toilets.

Porcelain toilets are more common in bigger RVs – Class A and Class C vehicles. Plastic toilets, on the other hand, are often installed in trailers and campervans.

Porcelain RV Toilet

The second one is the flushing – household toilets usually have a handle on top of the toilet. With RV toilets, it’s more common to have a pedal at the bottom.

This is because RV bathrooms are usually super small and cramped and reaching a pedal on the bottom of the toilet is quite easy. However, where that waste goes depends on the type of toilet you have in your RV.

A classic household toilet is connected to your home’s plumbing system. It draws water into the holding tank that stays there until you press on the flushing handle. This action flushes the waste in the toilet, sending it to the town’s sewage system. Well, RV toilets are very similar, except for the sewage system. Instead, the waste collects in your RV waste tank (if you’re using a flushing toilet), or in the toilet’s waste tank (with self-contained toilets).

That’s the third key difference – with RV toilets, you’re the one cleaning the sewage after yourself and others.

In addition to that, some toilets don’t flush at all. These are either self-contained toilets that have dedicated waste tanks, composting toilets, or very portable toilets that use disposable bags to collect waste. Composting toilets are quite common in RVs, whereas the other two types are more often used by campers and hikers. But they can work just fine for an RV in a pinch.

Type Of RV Toilet

There are a few different types of RV toilets and they all work in different ways. I’ll cover both flushing and composting RV toilets and explain the main similarities and differences between the ways they work. I’ll also mention portable toilets that are more popular in campervans and caravans, especially in the smaller vehicles that don’t have enough room for a full bathroom.

Composting Toilet

kildwick miniloo in van complete

Composting toilets are most popular with campers who really want to avoid producing toxic waste. They don’t need a plumbing system to work because most composting toilets don’t have a flushing system. Instead, the waste decomposes over time, and it eventually turns into fertilizer.

When you want to go number one, you just use the toilet normally. But when you want to go number two, you’ll need to pull a lever that opens up the dedicated solid waste tank.

There are pros and cons to having a composting toilet in your RV. The main pro is that you don’t need plumbing, so you can save a lot of water. The eco-friendliness is also an upside, plus they can’t get clogged.

kildwick miniloo waste tanks

The downside of the composting toilet is that you can’t connect it to an RV black tank. Instead, composting toilets usually have two waste tanks – one for liquids and another one for solids. The tank with liquids can usually be emptied into any public toilet, just don’t forget to clean up after yourself. The tank for solids, on the other hand, should always be emptied according to local laws and regulations.

The frequency at which the tanks need to be emptied depends on how often you use the toilet, much like with the RV waste tank.

Also, composting toilets don’t really smell that bad. Most composting toilets have small vents that keep the compost dry while the bacteria break down everything. Plus, the solid waste is usually in a closed tank, so most of the odor is just contained inside.

Classic RV Flushing Toilet

Flushing RV Toilet

The most common type of RV toilet is a flushing toilet that connects to RV plumbing. These toilets use water from the freshwater tank to flush, and they empty into the RV waste tank. They’re by far the most convenient type of RV toilet and they’re generally the most affordable option, especially if you skip the pricey porcelain.

Plastic toilets are an alternative to porcelain. They are lighter and more affordable, but not quite as durable and sturdy. Also, plastic toilets have a maximum weight limit, and it’s usually around 300-400 lbs.

You can use them just like regular toilets, with the main difference being the position of the flushing handle/pedal. Also, with RV toilets, you have to get rid of the sewage on your own (empty the waste tank), as opposed to just letting it flow into the city sewage network.

One thing worth noting here is that it’s recommended to use single ply toilet paper with RV toilets. It decomposes quickly and easily, as opposed to three-ply toilet paper, which can clog the toilet and waste tank.

Portable Toilets

Portable Toilet

The third type of RV toilets is portable toilets. They’re not fixed to the RV, and they’re a great option for people who spend more time outdoors than in the RV. These are more popular with campers and people who don’t have full bathrooms in their campervans, especially because they are cheaper and lighter than standard RV toilets. Also, you can just keep store them out of the way and bring them out only when you need to use them, which is super convenient for travelers in cramped campervans.  

These toilets are usually self-contained, with the option of choosing between a flushing and a non-flushing toilet. You usually can’t connect them to a plumbing system – instead, you must manually add the water to the tank before you flush. You must also empty the waste tank on your own.

Portable toilets also have better water efficiency than flushing toilets. Some even feature a double-action pedal, with a light flush for number one and a more thorough flush for number two.

The downside of having a portable toilet in your RV is that you need to empty its tank more often than you would have to dump an RV waste tank. Also, these are generally smaller than normal toilets, and they’re not that comfortable.  

Emptying The Waste Tank

Oh yay, it’s time to empty the waste tank – said no camper ever. I always get a flashback from the RV movie with Robin Williams, when he’s trying to empty the tank end winds up showering himself and everyone around him with waste. And that’s why I’m always extra cautious when emptying the waste tank. In case you missed the movie, here’s something to make you terrified of emptying your RV waste tank for the next decade or so: 

When you flush a toilet, all the waste goes into the RV black tank. Some RVs also have a gray tank, which holds the water from sinks and showers – if your RV doesn’t have a separate gray tank, then all the waste is accumulated in the black tank.

It’s important to note here that waste should only be dumped at marked RV dump sites. You should always wear gloves when dumping the black tank, and be cautious with the valves. When you’ve emptied it entirely, it’s always a good idea to sanitize the black tank before it gets filled up again.

However, don’t go too crazy with the chemicals – adding a lot of chemicals to the RV black tank makes your waste toxic, which is something most RV dump sites forbid. Because of this, it’s recommended to use biodegradable cleaning agents to sanitize both the toilet and the black tank.

How often should you empty the black tank? That depends on how often you use the toilet, the number of people that you are traveling with, and the size of your RV black tank. If you’re traveling with a group of people and you all use the toilet a couple of times a day, you will likely need to empty it every other day. But if it’s just you and your partner, once a week should be more than enough.

Also, some RVs have sensors inside the tanks that let you know exactly how full they are. These can make your life much easier, but they only work properly for the first few years. After that they’re much less accurate, so you can’t always rely on them entirely. 

About the Author Anna Timbrook

Anna is the co-owner of expert world travel and can't wait to share her travel experience with the world. With over 54 countries under her belt she has a lot to write about! Including those insane encounters with black bears in Canada.

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