How Does An RV Toilet Work?
An RV toilet and a residential toilet are similar in many ways; however, there are some intricacies when it comes to the RV toilet that one has to understand in order to use it properly and to avoid any “user error” damages.
The RV toilet is a fairly simple assembly, despite its intimidating stigma of the “dumping poop”. The scary reputation comes mainly from Hollywood movie comedies, such as “RV” with Robin Williams.
While the process of emptying the black tank and caring for the RV toilet system might be a bit intimidating to those who are new to the RV lifestyle, with a little education, those fears and hesitations can be quickly neutralized.
The biggest difference between an RV toilet and a residential toilet is that the RV toilet is “self-contained” unless attached to the septic system. This means you have to understand the mechanics of the flow from the toilet into the black tank and then the process of emptying the black tank once full.
A secondary difference between an RV toilet and a residential toilet is a design issue: RV toilets are sometimes made of plastic (largely due to weight preference and more sturdiness when traveling) and they have a foot pedal to flush, rather than a flush tank mechanism.
When you flush the RV toilet, the flush pedal mechanism opens the flap that divides the toilet from the black tank entry, and the water sprayer rinses out the toilet bowl, flushing down the waste into the opening, assisting with the freefall of the waste into the black tank.
The black tank is the human waste holding tank that is located in the underbelly of the RV. It has a specific capacity, which depends on the size of the RV and the designed RV occupancy rate. For example, an RV for up to 9 people has a black tank capacity of 43 gallons (https://www.granddesignrv.com/showroom/2022/fifth-wheel/reflection/floorplans/28bh).
You have to empty the black tank once it’s over ⅔ full. The process will be explained below in the specified section.
A toilet wand is a tool that you can use to keep your black tank clean and minimize waste buildup that can lead to costly clogs and repairs. You can easily build your own or purchase one: https://www.amazon.com/Camco-40103-Holding-Rinser-Valve/dp/B00QTOPTIO/ref=sr_1_9?keywords=rv+toilet+wand&qid=1661524579&sr=8-9.
The wand allows you to reach and rinse hard to get-to places in the black tank area, such as the black tank walls where the sensors are located. These get often coated with dried on waste or TP chunks, making them unusable.
Types Of RV Toilets & How To Use Them
There are different types of RV toilets on the market today:
- Traditional Gravity Flush. This is the most common one and uses a mix of gravity and water to flush the waste.
- Macerating Flush. This one is more elaborate and has a macerating assembly that turns solid waste into slush. It requires electricity to run.
- Dry Flush. This one only uses gravity and no water.
- Incinerator Toilet. Uses electricity to burn and dry waste. Requires venting.
- Vacuum Flush. This one uses a vacuum flush and a macerating system.
- Composting Toilet. This one is good for one person to use, as it can get smelly if not used properly or overused.
- Portable Toilet. Fully portable, easy to use, can get smelly.
- Cassette Toilet. This is a portable toilet. You remove the bottom portion to empty.
Thetford and Dometic are the leading brands in the RV toilet business and provide traditional gravity flush toilets to the majority of newer RVs.
Keystone RV has a series of educational videos for new RV owners that explain RV use and maintenance concepts, such as this short video that explains “How to use the RV toilet properly”:
What To Do Before Using The RV Toilet?
There are few small differences between a residential and an RV toilet, and for that reason there are just small intricacies when using an RV toilet.
- Make sure your black tank valve is CLOSED, unless you are connected to a septic system (still, the preference is to have the black tank closed until it’s time to empty it).
- Use RV toilet paper
- Close the lid before you flush (preferred)
- Use your foot to press the flush pedal
- Flush twice or for a couple seconds
- If not done already, close the toilet lid. It keeps the smell etc. at bay, as there is just a simple flap that’s the barrier between your RV space and the black tank access.
How To Connect RV Toilets To A Sewer
To connect the RV toilet system to the sewer, make sure you have the appropriate sewer hose attachments. Many new RVs come with a “Welcome Kit” that has a short sewer hose included, but it is advisable to purchase a longer heavy-duty sewer hose, along with a clear 90-degree elbow.
If budget is not an issue, there are also additional tools one can purchase, like the sewer hose rinser and sewer support (Camco Sidewinder).
Follow these steps:
- Locate your black tank sewer hose connection.
- Put on nitrile gloves (if preferred)
- Take out the sewer hose assembly and attach the sewer hose to the RV sewer port.
- Attach the other end to the sewer drain hole (usually in the ground, sometimes raised an inch or two off the ground, depending on dump station or RV park site)
- Make sure the sewer hose is secured on both ends (at RV port and at the sewer hole). This is important. A clear 90-degree elbow is handy to see the flow of the waste, and it also secures well into the sewer jole without an awkward bend in the sewer hose.
- Dragging the sewer hose over gravel etc can cause damage to the sewer hose and leaks, so make sure you carry the hose, support it properly and create a gravity downward flow from RV port to the dump hole.
- Once the sewer hose is secured, open the black tank valve. This is usually a pull-valve. Make sure you open it fully. Leave it open while the black tank contents are emptied.
- Once the flow is a mere trickle, use the backflow hose to rinse out the hose and/or black tank (if applicable). Leave some water in the black tank when finished. You can do this by closing the black tank valve for a couple of minutes and filling up the black tank with the backflush water.
- Once the valve is closed, you can remove the sewer hose at the RV port and hold it to drain out anything that still remains in the hose. Some RVers empty their gray tank after their black tank, which allows for the hose to be rinsed out with “less gross liquids”. You can also rinse out the sewer hose with a water hose. Make sure you have a designated water hose for this, as you don’t want to cross-contaminate.
- Remove the sewer hose from the sewer hole and stow it away. Some people use trash bags or totes, while some RVs have designated sewer hose channel storage.
If there is no sewer hookup at the campsite, you will have to either empty your black tank into a portable tank and haul it to a dump station, or take your RV to a dump station in your area. Do not dump your black tank waste into public rain drainage areas or just anywhere. Not only is that gross, but it’s also a biohazard.
Proper Maintenance Of RV Toilets
A few tips in summary to make sure your RV toilet system is happy and serves you well for a long time without issues:
- Flush twice or for a couple of seconds. Water in the black tank is your friend.
- Don’t leave the black tank open. Make sure it’s at least ⅔ full before emptying it.
- Use RV-safe toilet paper and cleaning supplies.
What Toilet Paper Is Safe For RV Use?
RV and Marine toilet paper is biodegradable and fully dissolvable in water whereas regular TP takes much longer to dissolve and can even build up. Because the black tank is so small, the TP does not sit in liquids to disintegrate as long as regular TP would in a home septic system.
While some RVers claim they have used regular toilet paper in their RV, most manufacturers and technicians do not recommend it. While the RV toilet paper is much pricier, it saves costly repairs of black tank buildups and vent clogs.
Some of the RV toilet paper brands are:
- Thetford Campa RV
- Scott RV and Marine (one can find deals with 4-pack for $3)
- Camco RV TST 2-ply
- Valterra Q23640
- Freedom Living Septic Safe RV TP
- Bamboo Toilet Paper
When using RV TP, keep in mind it’s much thinner, but you still cannot and should not overuse the TP by triple- and quadruple folding. If at all possible, try to use it conservatively, 3 squares per wipe.
Finally, there is a faction of RVers who use regular TP but don’t flush it into the black tank; they have a trash receptacle in the bathroom for the TP instead. Other options include wet wipes and bidet install.
What Toilet Bowl Cleaners Can You Use In Your RV Toilet?
There are several RV-use exclusive products on the market, but there are also everyday household products that are safe for RV toilet use.
The two biggest things to consider about cleaning supplies in the RV are: abrasiveness and biodegradability.
Some RV toilets are plastic, although many RV manufacturers have moved to ceramic toilets. In that case you mostly have to worry about the biodegradability of your cleaning supplies. However, if you have a plastic RV toilet you have to ensure that your cleaner’s chemicals do not interact adversely with your plastic toilet surface. The damage can be discoloration, toxic fumes, all the way to melting due to chemical reaction.
Some of the RV toilet cleaners available on the market today include Dometic 3-1-toilet bowl cleaner, Unique RV toilet bowl cleaner and black tank rinser, Eco-Me or Star Brite.
The best cleaner is one you can use safely and one that is multi-purpose so that you don’t have to haul several different products along.
Of course, the ceramic toilet is more forgiving on the abrasiveness spectrum, but ideally, most RVers still choose products that do not harm their black tank in the long haul and products that are safe for the environment, as well as their personal health.
Sincel the goal of toilet cleaning is to minimize germs and bacteria that cause unpleasant odors, everyday household products such as vinegar and Dawn are OK choices. Try to stay away from bleach-based products, such as Lysol, however. Not only are they corrosive for your RV, but these are also cancer-causing. Stick with mildly acidic or alkaline (baking soda) natural cleansers. You will save money and your health.
Can you flush toilet paper or wipes in an RV?
No! Unless you want to risk clogs, cumbersome and expensive repairs, try to stick with RV toilet paper and don’t go wild with the usage.
What can you use to unclog your RV toilet?
The best and most effective thing to use to unclog your RV toilet is a black tank cleaner, as this chemical dissolves human waste, as well as the RV toilet paper. There are also powerful bio-enzymes that are available and they break down the waste into a liquid slush.
How often should you dump your black water tank?
The black tank should be emptied when it’s at ⅔-¾ full. On average, that’s every 3-5 days, depending on use and occupancy rate. When storing your RV, make sure the black tank is empty and cleaned (backwashed and/or rinsed).
Can you use Poo Pourri in an RV toilet?
While the Internet opinion verdict still seems out on this one, as it is a fairly new-to-the-market product, some RVers swear by it. The company claims it’s safe for the RV toilet and the black tank. As with any newer products, customers using it in the field over a long period of time become the test group. So far, there are no issues with the use of Poo Pourri in RV toilets.
Can you use a plunger on an RV toilet?
Yes, you can use the toilet plunger just the same as you would use it on a residential toilet.