5 Reasons Why Your RV Toilet Bubbles When You Flush

If you have noticed your RV toilet bubbling when you flush, then you need to know what can potentially be causing it and how to resolve it. A toilet bubbling in an RV can be an indication of a problem, and if you let it go too long, it may result in more damage and costly repairs. 

Why does my RV toilet bubble when I flush?

The toilet bubbling in your RV when it is flushed could be due to the blank tank being full, a blocked drainage pipe, solid waste buildup, debris buildup at the bottom of the tank, or the blank tank vent being blocked.

Your black water tank is critical to your RV plumbing system running properly so you need to know how to troubleshoot and resolve any issues that come up, especially if a problem arises while you are out on the road. 

Knowing how to properly resolve issues with your toilet bubbling can allow you to quickly fix the problem. The information in this guide has been provided by experts in the RV industry and is accurate information in order to inform you how to resolve the issue if it happens. 

Reasons Your Toilet Bowl Bubbles When You Flush

Black Tank Full

One of the most common reasons for your RV toilet to bubble when flushing is that your black tank is completely full. 

If the black tank gets too full, it can potentially back up into your toilet. It is important to regularly check your black tank and ensure that you are emptying it regularly. 

Blocked Drainage Pipe

If the drainage pipe is blocked then it can cause the toilet to bubble. If you know your black tank is not full, you can check the pipe and sewer hose. The sewer hose is more flexible and is not likely to clog, but because the drainage pipe is a solid pipe there is a chance of it getting clogged.

If you have checked and the drainage pipe is clogged then you will need to unclog the pipe in order to get the water to flow properly again. This can be done by using an RV tank cleaning wand and trying to push the blockage into the tank or you can also try dumping boiling water in to break up the blockage. 

Solid Waste Buildup

Even if your black tank is not completely full, it can still have solid waste buildup. If you have checked your black tank and emptied then it could very likely be that there is solid waste that did not get dissolved or swept away. 

Sometimes this could be due to a buildup of toilet paper or even potentially something that should not have been flushed down your RV toilet and has now created a buildup. 

Black Water Tank Vent Blocked

If none of the other issues seem to be the problem then you could potentially have a blockage in the black water tank vent. 

The vent ensures that air exits properly when the toilet is flushed and the black water tank is refilled. A blockage of the vent may be caused by leaves or, commonly a bird creating a nest that blocks it.

This is a simple fix as you can just remove whatever is blocking the vent. After removing whatever is blocking the vent you will want to thoroughly clean it as well. 

Debris at Bottom of Black Water Tank

If there is debris that has collected at the bottom of the black water tank, this can eventually cause the toilet to bubble when flushed. 

It is common for debris to build up, especially at the drain pipe opening. This is treated as you would if the drainage pipe is clogged. You can use an RV tank cleaning wand to try to remove the debris as well as attempt to pour boiling water to help move the debris out of the way. 

What Is The Black Water Tank?

If you are living in your RV then you probably know about the different water tanks. The black water tank in your RV is what holds the waste contents from the toilet. However, the gray water tank will hold the water that comes from the sink and shower. 

When speaking about water in an RV you will probably hear both tanks mentioned. Typically, most RVs have sensors that will alert you when your tanks need to be emptied. 

It is best to empty your black and gray water tanks when they are approximately 75% full. If you wait too long, it can be as simple as one toilet flush that causes the tank to overflow. 

Why Is My Camper Toilet Gurgling?

There are certain actions that can be taken that will help prevent having issues with the black water tank and to prevent your camper toilet from gurgling. 

Empty Tank Regularly

To prevent the black water tank from getting too full or getting solid waste buildup, it is critical to empty the black water tank as often as you can. 

It is a good idea to empty the black water tank after every trip you take or every few days if you are consistently traveling. You will want to pack up the RV including moving all slides in, find a dump site, and be sure to dump it in order to keep it from filling up too much. 

Once you find a dump site, it is a good idea to wear disposable gloves when emptying your black water tank as well as close-toed shoes in order to prevent stepping in anything or getting something on your hands. 

If it does get too full or gets solid waste buildup, you can always run fresh water through it in order to flush the system. 

Treat Your Black Water Tank

If you empty the black water tank but are still having issues then it might be time to treat the black water tank. 

You can purchase a black water tank cleaner that will help remove any blockage and build-ups from your black water tank. It is a good idea to periodically use a black water tank cleaner in order to thoroughly clean the black water tank. 

It is a good idea to treat your black water tank monthly especially if you continue to have issues with blockages or debris building up in the tank. A simple monthly maintenance schedule can help to prevent issues in the future. Your RV has other maintenance that will need to be completed on a regular basis so it is a good idea to include the cleaning and treating of the water tanks into the schedule.

Regularly Check Black Water Tank Vent

The black water tank air vent is a good item to check before each trip you take with your RV. It can become clogged with leaves, debris, bugs, and other things. 

If you find it is clogged then you can use a snake hose attachment to remove anything that is blocking it. In the event that the snake hose attachment does not remove what is clogging the air vent then you can use a hose to spray water and the added pressure should help you to get it clean. 

By regularly checking the vent, you will know if you run into issues that this is not the source of the problem.