RV Toilet Valve Stuck Open – Why It Occurs and How To Fix It

The RV toilet valve stuck open happens often, and a handful of factors cause it. Fortunately, these causes are easy to fix and require little to no experience or training.

RV Toilet Valve Stuck Open

We’ll discuss how the valve gets stuck and the most practical ways to fix it. We’ll then answer some pertinent questions regarding RV maintenance at the end of the article.

What Causes the RV Toilet Valve To Get Stuck Open?

The causes of the RV toilet valve getting stuck open is due to a defective water valve, problematic foot pedals, and issues with water flow. These problems can easily be solved by replacing or fixing the affected components. Better still, you can prevent these issues with proper maintenance.

A Malfunctioning Water Valve Blocking the Water Flow

The valve’s duty is to allow water into the tank as soon as the water drops below a certain level. Once the water fills up to that level, the valve automatically shuts off, stopping the water from overflowing the tank and messing up the place. The water either comes from the freshwater tank or the city connection. A defective valve will allow water to pass through the toilet bowl into the black tank, wasting the water. 

This can be frustrating, as the water supply in an RV is limited, and getting water to refill the tank can take a while. One way to detect a defective valve is water flowing into the toilet bowl when you’ve not pressed the foot pedal. There are two ways to solve this problem: fix the valve with DIY methods or replace it with a new one. We’ll discuss how to approach both methods; keep reading.

A Defective Foot Pedal Getting Stuck to the Floor

The foot pedal serves as the flush button on a home toilet system. Once you’re done using the toilet, you depress the foot pedal, which allows water to flush the sewage into a waste tank. This tank is usually located under the RV, and it’s called a waste water tank or RV black tank, which has a black tank valve. When the foot pedal is pressed, it sinks to the floor, opening up the valve for the water to flow and then rises again to cut off the water flow.

Causes the Faulty RV Toilet Valve

However, a faulty foot pedal might sink to the floor and get stuck. This, in turn, leaves the valve stuck open, allowing the water to flow unceasingly into the blackwater tank. Sometimes, the pedal can become stiff, making it difficult to depress it. When this happens, the valve remains closed, preventing the water from flushing the waste.

Either way, you’ll have to repair the pedal or replace it with a functioning one. We recommend you replace the foot pedal because repairing it might not last before the problem recurs.

Water Flow Problems from City/Campsite

Sometimes some RV owners try to save water in their vehicles by connecting to water hookups whenever they’re in the city. This helps to save some money and helps them stay longer on the road. In fact, if you have many passengers on board and water won’t be enough, we strongly suggest you make use of these water hookups. However, there are a few problems with using this water-saving strategy.

First, the city water flows with irregular pressure and fluctuations. One moment, the pressure is so low that the water is struggling up your pipe. At another moment, the pressure is so high that it could flood your RV if you don’t turn off the water supply. Thus, when you’re connected to city water and see water constantly flowing in your toilet bowl, the problem might not be the foot pedal or water valve. The water pressure is probably too high for your toilet system, causing it to flood.

How To Solve RV Toilets Valve Stuck Open?

To solve RV toilets valve stuck open, remove the faulty valve and replace it. Another way is to try to repair the valve. However, if the valve isn’t faulty, check other parts of the system causing it to remain open and fix them.

Replacing an RV Toilet Valve Which Is Stuck Open

Always turn off the water supply to the RV toilet system before working on it to avoid spilling it on yourself and the RV. Next, disconnect the water supply hose but ensure you have a bucket or cup around to catch water from the hose. Once you’re done, loosen the bolts holding the toilet bowl in place with a suitable wrench. Now, turn the toilet bowl around to enable you to access the valve assembly.

Solve RV Toilets Valve Stuck Open

Remove the old toilet valve assembly by unscrewing the small bolt attaching it to the bowl, and sliding up the metal rod near the assembly. If stuck, use a screwdriver to pry it out of position. Install the new valve assembly in the same position as the old one and slide the metal rod down. You can take a picture of the old valve assembly’s position to help you know exactly where to fit the new one.

Screw the small bolt that held the old assembly into place and place the toilet bowl on the mount. Ensure the holes on the RV floor align perfectly with the toilet bowl before screwing it into place. Screw the lock nuts tight until the toilet flush rests on the floor, and reconnect the water supply hose. Finally, reconnect the water supply to the RV system and flush the toilet to ensure the new valve works properly.

Cleaning Debris/Dirt from a Foot Pedal

Sometimes the toilet valve could be stuck open because debris may have collected in some areas, preventing it from closing the water valve. Thus, you’ll need to clean the foot pedal to get it to rise and shut off the toilet valve. Fortunately, cleaning the foot pedal is a walk in the park.

All you need is a toothbrush or a small paintbrush with hard bristles. Examine the entire foot pedal and identify areas that are saturated with debris. Clean them with the toothbrush and wipe them with a towel. Now, test the foot pedal to see if it’s working properly. If it’s not, the foot pedal is broken and needs replacement.

Ways To Replace a Defective RV Toilet Foot Pedal

Before beginning with RV toilet foot pedal repairs, ensure you have a towel to clean up in case there’s a leakage. Next, remove the tank by unscrewing the nuts holding it in place, and then detach the toilet bowl from the RV floor. Pour any remaining water out of the holding tank and place it, alongside all the other components, on a nearby table. Remove the old defective pedal and insert a new one in its place.

After installing the new pedal, connect its arm to the top of the RV’s toilet bowl. Now, reattach the toilet bowl to the floor, ensuring that the holes on the bowl align perfectly with the ones on the floor. Once the toilet bowl is installed, screw the new foot pedal tightly into place so it doesn’t break. Fix the water tank back to its original position and close it.

Test the new foot pedal to ensure it is working correctly by turning on the water supply and depressing it. If it works, then your problem is solved, but if it doesn’t, you need to enlist the help of an RV specialist.

Solving Water Pressure Problems

To solve the water pressure problems that occur when you’re connected to city water, purchase a pressure regulator. The regulator ensures that you get the same water pressure, whether there’s a drop or a surge in the psi. It works alongside a water booster to raise the water pressure throughout the RV when it falls. However, the pressure problems may not be from the city water supply but from your RV.

Thus, you have to perform some checks to locate the source of the problem and correct it. For example, a bend in the rubber hose could cause a drop in the water pressure. Thus, straightening the bend would bring the pressure back to its “normal” level. Another factor that can decrease water pressure is a clogged filter.

Water filters need to be changed every 6 months to ensure you get clean drinking water when you’re far away from home. Also, malfunctioning RV water pumps can affect the flow of water through all the connections before it gets to you. Thus, you’ll need to test it to see if it is performing below its capacity and replace it. Finally, you can check for leaks along the RV’s pipeline because they can affect the rate at which the water flows. 

Frequently Asked Questions

How Do You Solve an RV Toilet Valve That Is Stuck Closed?

To solve an RV toilet valve that is stuck closed, you need to check the exact cause of the problem. If the water or the ball valve is malfunctioning, replace them. If water gets into the foot pedal and gets frozen, you’ll need a heat source for defrosting.

Replacing an RV Toilet Valve

What Are the Possible Reasons for an RV Toilet Valve to Get Stuck Open?

When an RV toilet valve gets stuck open, several possible reasons for gas tank won’t fill need to be considered. It could be due to a faulty valve mechanism, debris or a blockage in the valve, or even a problem with the water supply. Additionally, issues with the fill hose or the tank vent can also cause the valve to remain stuck open.


An RV toilet valve getting stuck open shouldn’t give you sleepless nights as the solutions are easy, and you can do them yourself with little DIY skills.

Here’s a recap of all that we’ve discussed:

  • A dometic RV toilet valve won’t open when the valve itself malfunctions, causing the water to flow through the toilet bowl into the black water tank.
  • A defective foot pedal can get stuck when it is pressed to the floor allowing the valve to open and causing the water to flow.
  • Water pressure, especially when connected to the city water, can overwhelm the RV’s pipe system and cause it to overflow, flooding the RV.
  • To fix the toilet valve, remove the old one and install a new one according to the instructions explained in the article.
  • If you’re experiencing water pressure problems, you can install a water pressure regulator and booster to keep the rate at which the water flows constant.

Another reason the water pressure has dropped could be a leakage in the pipes and hoses of the RV; thus, conduct a thorough check to identify the leaks and seal them. Also, change the water filter after 6 months of use because a clogged filter can cause a drop in water pressure.

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