How Do RV Toilets Work? [I was Surprised]

RV bathrooms provide privacy that you can’t find while backpacking or camping with a tent. Most RVs have at least one bathroom, with some of the larger ones having two. RV toilets come in all different varieties and functionalities. When using a home toilet, it seems simple. You do your business and flush the toilet. An RV toilet is not so simple due to the fact you are not connected to a sewage line. Let’s find out how RV toilets work, and which one is best for your RV.

Quick Answer

RV toilets use flush systems that are one of the following: gravity, macerating, vacuum, cassette, portable. Most RV toilets use a pedal system to flush waste into a tank referred to as the black water tank. Once the toilet has been flushed, the waste is stored in the black water tank until emptied. Campgrounds have dump stations or sanitation stations where the black water tank can be emptied. After emptying the tanks, it’s suggested to run fresh water in the toilet to help clear out remaining waste.

RV toilets work in the following way:

  1. Use the toilet
  2. Use pedal on floor to open valve and flush waste into black water tank
  3. Let off pedal to close valve
  4. When black water tank is full, empty it at a dump station using hose
  5. Run fresh water in the toilet to flush remaining waste and prevent odors
  6. Disconnect hose and rinse/store
  7. Flush toilet to get some water into black water tank
  8. Add any waste-treatment products to black water tank

RV Toilets: Everything You Need to Know

If you’re new to the RV world, you may have some questions about how RV toilets work. It may seem daunting having to empty tanks and deal with cleaning your toilet, but once you understand how it works, emptying the tanks will be just another step in your set up and tear down of camp.

How Do They Work?

There are five main types of RV toilets, each working in a different way. However, they all have some kind of holding tank that captures the waste and must be emptied when full. Tanks can be emptied at campgrounds using a hose, or if it’s a portable toilet it can be emptied in a regular toilet. Here’s how it works:

The bathroom: Most RVs will have a small room with a closed door that will hold a toilet, sink, and a shower. Some of the smaller campervans may not have a separate room, but have a permanently installed toilet over a small waste tank. Some have gotten very creative to hide these toilets under benches or regular seating. With proper planning, you can hide your toilet in a campervan and avoid any odors.

Flushing: Unlike toilets in a home, RV toilets do not have a handle to flush. Instead, they use a floor pedal that can be pressed with the foot. This flushes water into the toilet to wash down waste into the black water tank. Another type of flushing system is an electric remote or switch that is used to flush the toilet. Some RV toilets, such as portable toilets, do not have a flush system but rather have a very small holding tank directly beneath the toilet that gets disconnected and emptied.

Tanks get full: After so many uses, the black water tank will need to be emptied. The black water tank is usually emptied at the same time as the grey water tank, which receives the water from the kitchen and bathroom sinks. It’s a good idea to empty the black water tank before leaving a campground to reduce the weight of your RV.

Empty the tank: To empty the black and grey water tanks, simply connect the sanitation station hose to the connection point on your tanks. Open the valve for the black water tank and the waste will flow into the sanitation station. Next, empty the grey tank. Emptying this second will help flush any remaining waste from the hose, making cleaning easier. It’s recommended to wear gloves while emptying the tanks.

Getting ready for the road: Once the tanks are empty, flush fresh water through the toilet with the valves still open. This will remove any remaining waste, helping to eliminate odors. Close the valves and then rinse and store the sanitation hose. Flush the toilet once to fill the black water tank with some water. Add any waste-treatment you may use to the black water tank and close the flap and lid before hitting the road.

Five Different Types of RV Toilets

The five most popular types of RV toilets include the gravity flush, macerating flush, vacuum flush, cassette toilet, and the portable toilet. Each use a slightly different flush system that is unique and has its own advantages.

  1. Gravity flush toilet: A gravity flush toilet is one of the simplest RV toilets. It’s placed directly over the black water tank. A pedal flush is used to flush contents directly into the holding tank. Because of its need to be located directly over the holding tank, the location of a gravity flush toilet may be limited.
  1. Macerating flush toilet: The macerating flush toilet uses motor-powered blades to thin and soften waste into a slurry. This results in a more fluid content in the black water tank, preventing solids from mounding. It also makes emptying the tank easier as the waste will be more fluid. Macerating toilets can be positioned apart from the black water tank, giving you more options for bathroom location.
  1. Vacuum flush toilet: Similar to the macerating toilet, a vacuum flush toilet macerates the waste before it enters the black water tank. A vacuum flush toilet also uses a powerful stored vacuum that removes all the waste in the toilet bowl. This type of toilet does not need to be placed above the holding tank, so it can be located anywhere in the RV.
  1. Cassette toilet: Cassette toilets and portable toilets are typically used in campervans or smaller RVs. A cassette toilet is installed permanently over a waste tank, similar to the gravity flush toilet. In order to empty a cassette toilet, you will have to manually remove the holding tank and empty it into a sanitation station or a standard toilet. Usually, the holding tank can be accessed from outside the RV.
  1. Portable toilet: A portable toilet is similar to a cassette toilet except it is usually not accessible from outside the RV. It is easy to install and lightweight, but because of the small holding tank it has to be emptied frequently. The tank must be manually emptied, meaning you will see and smell the sewage as you empty it.

Which Toilet Is Best for Your RV?

Every RV toilet has its own advantages to fit your specific RV needs. Whether you need one that’s water conserving, easily emptied, or one for limited space, there’s an RV toilet that will work for you.

Easiest to empty: Vacuum and macerator toilets are the easiest to empty due to the motorized blades that make the waste more liquid. When emptying through the hose, the more liquid waste will make emptying the tank much easier than say a gravity flush toilet.

Uses the least amount of water: Gravity and vacuum toilets use the least amount of water. Both of these toilets us food-pedal flushing systems, which tend to use less water than an electric flushing system. Some of the more advanced electric systems will offer a ‘normal’ and ‘low’ setting for water consumption. But, in general, foot-pedal operated toilets use less water.

Easy to use in remote areas: If you’re planning on travelling somewhere remote where you won’t have access to electrical power, a cassette or portable toilet will be your best bet. These toilets rely on their own water reservoir to flush the toilet, meaning you don’t need hookups. They are also emptied manually, so you will not need a campsite’s sanitation station to empty them, just a standard toilet.

Best for tight spaces: If you don’t have a ton of room for your toilet, a cassette toilet offers easy placement with a small footprint. Vacuum and macerating toilets also come in compact ped-flush versions. The great thing about vacuum and macerating toilets is that they do not have to be placed directly over the waste tank like cassette toilets, so placement of these toilets is easier and less complicated.

The best of the best: If you’re not concerned about space or price, consumers say the vacuum toilet with a high-profile, full ceramic finish and slow-close seat is the best toilet. It has the most powerful flush, which means it will be virtually odor-free. The vacuum toilet uses only a small amount of water and electricity. With the motorized blades that make waste more liquid, it is also fairly easy to empty.

There are many options to choose from when it comes to your RV toilet. Each have their own specific advantages that might fit your specific needs. Understanding the different types and what is involved will help you make an informed decision when choosing the right toilet.

Tips to Prevent Bad Odors

No one wants to be sitting in their RV’s living space and have a bathroom odor permeate the vehicle. Bathroom odors can be prevented in several different ways. Some toilets are more prone to emitting odors due to several factors, but they can be controlled with proper cleaning and treatment.

Use PVC pipe: If you have a vacuum or macerator toilet where the holding tank is not located directly beneath, you’ll need some kind of connection pipe or hose to funnel waste into the black water tank. If using a flexible hose, it’s possible for smells to permeate from the holding tank and up through the toilet bowl. PVC pipes will not hold such odors and can help eliminate pesky smells. If it’s not possible to use PVC pipes, simply make sure the waste hose drains properly in order to avoid any smells that might linger in the hose.

Keep flush ball/valve clean: When using a gravity flush toilet system, a seal and flush ball or valve is used to keep water in the bowl from leaking down into the tank. The water kept in the toilet bowl is what prevents odors from permeating outside the toilet. Keep the flush ball or valve clean and smooth in order to prevent this from happening.

Use tank treatments: This is especially apparent with cassette or portable toilet where the holding tank is located directly under the toilet. Treatment liquid or packets fight bathroom odors. Proper ventilation is also important for these types of toilets as it works with the tank treatment to eliminate permeating odors.

How to Empty A Black Water Tank?

This was touched on briefly earlier, but let’s look at a step-by-step process on how to empty a black water tank. Some important pre-empty steps include making sure you are located above the dump station, wear disposable gloves, and before opening any valves make sure all connections are secure.

Step 1: Locate the tank valves – This is where you will hook up the hose to empty your tanks. Usually, the grey and black tank valves are located near each other and will be near where your fresh water is hooked up. Once you locate these valves, make sure they are both shut. Locate the lid to the hookup hose and remove.

Step 2: Connect the sewer hose – Some RV users take advantage of a sewer hose support. This creates a downward slope to help with emptying the tank. Once this is connected (if you have one), attach the sewer hose to the end of your pipe line. Place the other end of the hose in the sanitation dump station.

Step 3: Open black water tank valve – Once the valve is open, allow the tank to completely empty. Close the valve when finished.

Step 4: Open grey water tank valve – it’s a good idea to empty the grey water tank after the black water tank to help flush any remaining waste in the hose. Close the valve when finished.

Step 5: Clean the tanks and hose – Some RVs come equipped with a tank rinse system. Use a garden hose and attach to the sewer tank rinse system. Open the black tank valve and turn the hose on. Make sure this hose is not your fresh water hose. When the water running to the septic is clear, you can close the black tank valve and do the same with the grey tank valve.

If you do not have a tank rinse system, simply unhook the hose from your tank attachments and run garden hose water through it. Again, make sure this is not your fresh water hose.

Step 6: Finish up – Once your tanks and sewer hose are clean, pack up your hose in your storage compartment, put the lid securely back on the tank outlet, and store your garden hose.

Can You RV Without A Toilet?

Yes. You can always RV without a toilet. However, this isn’t a great option if you plan to RV in remote locations or with other people. Additionally, having a private area to do bathroom needs makes camping and travelling less of a hassle and more enjoyable. Many RV bathrooms come equipped with a sink and shower as well, making travelling cleaner and more affordable than paying to use a bathroom or shower. Having a toilet in your RV is convenient because:

  • Do not have to plan for stopping at rest stops or gas station bathrooms
  • Can still travel to remote areas without electricity
  • Easy when travelling with more than one person
  • Most are very easy to empty
  • Saves time and doesn’t take up much space
  • If properly maintained, will not have odors
  • Gives privacy to you and guests
  • Can pick from a variety of toilets to fit your needs

Do You Have to Use Special Toilet Paper in an RV?

Yes. RV sewage systems are not as durable as the systems in our homes. Because of this, it’s important to use toilet paper that breaks down quickly and is biodegradable. This doesn’t mean you have to get RV-specific toilet paper, but make sure to use 1-ply toilet paper or something that breaks down quickly.

Wrap Up

RV toilets come in a variety of different set ups, flush systems, and tank systems. When choosing the right toilet for your RV, consider the amount of space you have, how easy you want it to be to empty the tank, and how large your black and grey water tank systems are. It’s not required to have a toilet in your RV, but it makes travelling more convenient. Now get out there and start exploring!

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