How to fix a running toilet: A step-by-step repair guide
Running toilets aren't just annoying, they're a waste of water. Stop a running toilet in its tracks with these simple repair steps.
Our experts independently review everything we recommend. If you buy through our links, we may earn commission.
A running toilet can mean more than just an annoying sound; it can also waste a significant amount of water and increase your utility bills. A running toilet can waste up to 200 gallons of water per day, according to Roto-Rooter , making it essential to address the issue promptly.
Fortunately, fixing a running toilet is a relatively simple task that most homeowners can tackle with basic tools and a little know-how. This guide will walk you through the steps to identify the cause of a running toilet and provide clear, actionable steps to fix it. Don't forget, you may need some handy DIY plumbing tools to assist you along the way.
Identify the cause
Before diving into repairs, you need to determine the source of the issue. According to local service review site Angi , the most common causes of a running toilet include a malfunctioning flapper, a faulty fill valve or a misaligned float. Mineral buildup or debris can also contribute to the problem.
To check this, start by removing the tank lid and inspecting these components carefully. Observe the water level, inspect for leaks and check for any obvious signs of wear or damage.
Inspect the flapper
A man works on identifying issues in a toilet tank
The flapper is a rubber valve that seals the water inside the tank until you flush it. If the flapper is worn out or not sealing properly, water will continuously flow from the tank into the bowl. According to Texas-based plumbing company Mother Modern Plumbing , flapper deterioration is a common cause of running toilets.
First, lift the toilet tank lid and locate the flapper at the bottom of the tank. Check for visible signs of wear, such as cracks, warping or mineral buildup. If the flapper is damaged, it will need to be replaced. To replace the flapper, turn off the water supply, flush the toilet to drain the tank, and disconnect the old flapper from the chain and mounting posts. Attach the new flapper, ensuring it fits securely over the flush valve.
Testing the flapper by adding a few drops of food coloring to the tank can help identify leaks. If the color appears in the bowl without flushing, the flapper is not sealing properly. This simple test can prevent unnecessary water waste and ensure that the repair is effective.
Check the fill valve
The fill valve controls the amount of water in the tank. If the fill valve is not working properly, the water level may be too high or too low, leading to continuous running. According to Lowe's , adjusting the fill valve can resolve many running toilet issues.
First, inspect the fill valve for leaks or signs of wear. Adjust the water level by turning the adjustment screw on top of the valve. Keeping the water level approximately one inch below the top of the overflow tube can prevent overfilling. If the valve is damaged, it will need to be replaced. Shut off the water supply, disconnect the water supply line, and remove the old fill valve. Install the new valve following the manufacturer's instructions.
If the fill valve continues to cause issues, consider investing in a high-efficiency fill valve. These modern valves are designed to minimize water waste while maintaining optimal water levels, making them an excellent long-term investment for homeowners looking to reduce utility costs.
Adjust the float
A man works on fixing an issue inside of a toilet tank
The float controls the water level inside the tank. If the float is set too high, water will overflow into the overflow tube, causing the toilet to run constantly. Better Homes & Gardens suggests adjusting the float to regulate the water level effectively.
First, check the float height by observing the water level. If it is too high, adjust the float arm by turning the adjustment screw or by bending the float arm downward. Test the flush to ensure the water level is at the proper height. If the float is damaged or unable to be adjusted, it may need to be replaced.
Some toilets use a float cup rather than a float ball. In these cases, the adjustment mechanism may differ slightly, but the principle remains the same. The goal is to maintain a water level that is about one inch below the top of the overflow tube. Maintaining the correct float position not only prevents water waste but also helps to avoid unnecessary stress on the fill valve, extending its lifespan.
Examine the overflow tube
The overflow tube prevents the tank from overfilling by redirecting excess water back into the bowl. If the overflow tube is too tall or too short, it can cause water to run continuously.
To start, inspect the overflow tube for cracks or misalignment. Adjust the height of the overflow tube so that the water level is approximately one inch below the top of the tube. If the tube is damaged, replace it following the manufacturer's guidelines.
Monitoring the overflow tube regularly can also help identify potential clogs. Debris can accumulate inside the tube, obstructing the flow of water and leading to overflow issues. Cleaning the tube periodically can prevent these problems and keep the toilet functioning efficiently.
Check the chain and handle
A plumber inspects the inside of a toilet tank for issues
A chain that is too tight or too loose can also cause a running toilet. If the chain is too tight, it may prevent the flapper from sealing properly. If it is too loose, the flapper may not lift when the handle is pressed. Adjust the chain length to ensure a proper seal.
First, examine the chain and ensure it has a slight slack when the flapper is closed. Adjust the chain length as necessary. If the chain is corroded or tangled, replace it with a new one. Using a corrosion-resistant chain can prevent issues in the future and ensure that the handle and flapper mechanism operate smoothly.
Reassemble and test
Once all components have been inspected, adjusted or replaced, reassemble the toilet tank and test for leaks. Turn the water supply back on, flush the toilet and observe the tank for any signs of continuous running.
Allow the tank to refill completely and wait a few minutes to ensure that the water level stabilizes. If the water level continues to rise or if the toilet continues to run, recheck the components to ensure that all adjustments were correctly made.
Fixing a running toilet: Identifying the source of the problem
A toilet in the process of flushing
Fixing a running toilet may seem like a daunting prospect, but with a step-by-step approach, it is manageable for most homeowners. Identifying the source of the problem (whether it is a faulty flapper, fill valve, float, overflow tube or chain) is crucial to effectively resolve the issue. If the problem persists despite following these steps, consider consulting a licensed plumber to ensure a thorough inspection and repair.
Additionally, routine maintenance can prevent future issues and save on water bills in the long run. Staying vigilant and addressing minor problems as soon as they arise can prevent more extensive damage and unnecessary water waste. If you need to get the pros involved, check out our full guide on the cost to fix common household plumbing problems .
