How to Fix a Toilet That Keeps Running
Common Causes and Solutions
A running toilet is a common household problem that can waste water and increase your utility bills. The good news is that it’s usually an easy fix that you can do yourself without calling a plumber. The three most common causes of a running toilet are a faulty overflow tube, flush valve, or fill valve.
Overflow Tube
The overflow tube is a hollow tube connected to the flush valve. It prevents the toilet tank from overflowing if the fill valve does not turn off. If the overflow tube is too short, water will continuously flow into the tank and out of the overflow tube. To fix this, replace the flush valve. The new flush valve must be compatible with your toilet.
Flush Valve
The flush valve is an assembly within the toilet that consists of an overflow tube, tank-to-bowl hardware, a tank-to-bowl gasket, a flapper, and a chain that connects to the flapper. The main purpose of a flush valve is to open the flapper to allow water to flow into the toilet bowl when the toilet is flushed and to close the flapper when the toilet tank is empty to allow the toilet tank to refill.
If the flush valve is faulty, it may not be able to properly close the flapper, which will cause water to continuously flow into the toilet bowl. To fix this, you will need to replace the flush valve.
Fill Valve
The fill valve controls water flow into the tank from the main water supply. If the fill valve is faulty, it may not be able to properly shut off the water flow, which will cause water to continuously flow into the tank and out of the overflow tube. To fix this, you will need to replace the fill valve.
Step-by-Step Instructions
How to Adjust or Replace an Overflow Tube
- Remove the tank lid and check if the water level is too high, causing it to run into the overflow tube. If it is, the water level should be lowered.
- Adjust the float rod or float cup to lower the water level inside the toilet tank.
- Verify the overflow tube height. If the overflow tube is too short, water will continuously flow into the tank and out of the overflow tube. To fix this, replace the flush valve.
How to Replace a Toilet Flush Valve
- Inspect the chain to make sure it is the right length to allow the flapper to fully close and open without extra chain.
- Inspect the flapper. If it is dirty or slimy, soak it in white vinegar and rinse with clean water. If it is warped or worn, replace it.
- Turn off the water to the toilet and drain the tank.
- Disconnect the flapper and remove the tank-to-bowl bolts to remove the old flush valve.
- Install the new flush valve.
- Test the toilet.
How to Replace a Toilet Fill Valve
- Verify the fill valve is faulty.
- Turn off the water and drain the tank.
- Unscrew and remove the assembly.
- Insert and adjust the new fill valve.
- Reconnect the water and test.
When to Call a Professional
If you are unable to fix the running toilet yourself, or if the water is overflowing or close to the rim of the toilet bowl while the water is running, you should call a plumber. It may mean an additional clog or another issue with the toilet.
FAQ
What is the most common cause for a toilet that keeps running?
The three most common causes of a toilet that keeps running are a faulty overflow tube, flush valve, or fill valve.
Will a running toilet eventually stop?
A running toilet will rarely stop on its own. Sometimes, jiggling the toilet handle will temporarily seal the flapper back into place at the bottom of the tank. But usually, you will need to replace a few parts to fix the problem.
What are the signs of a toilet going bad?
If you are constantly fixing the toilet, it always clogs, poorly flushes, you find cracks and puddles at the base, and it’s generally old, it’s time to replace the toilet.
