How to Fix a Running Toilet

Water waste in the bathroom usually starts with the sound of a toilet that never quite stops running. This phantom flush wastes gallons of water daily and eventually leads to higher utility bills if left unaddressed. Understanding the mechanical components inside your toilet tank is the first step toward reclaiming your quiet bathroom. Most running toilets suffer from a simple misalignment of the float or a degraded rubber flapper that no longer creates a watertight seal. This project requires no special training, just a clear look into the tank and a few minutes of manual adjustment. Once you learn the relationship between the fill valve and the flush chain, you will be able to silence any toilet in your home with ease.

1. See What's Inside. Remove the tank lid carefully and set it on a towel to prevent cracking. Observe the water level; it should be about an inch below the overflow tube without spilling into it.
2. Lower the Water Level. If the water is too high, locate the adjustment screw on the fill valve or slide the float clip down the rod. This lowers the water shut-off level so it stops before hitting the overflow pipe.
3. Test the Flapper. Reach into the tank and press down on the rubber flapper at the bottom. If the running water stops immediately, the flapper is worn or dirty and needs replacing.
4. Kill the Water Supply. Locate the shut-off valve behind the toilet and turn it clockwise until it stops. Flush the toilet to drain the tank completely before proceeding to repairs.
5. Swap the Flapper. Unhook the old flapper from the chain and the side pins on the flush valve. Snap the new flapper onto the pins and reattach the chain, ensuring there is just enough slack to allow a full flush.
6. Verify the Silence. Turn the water supply valve back on and wait for the tank to refill. Listen for the water to cut off completely once the desired level is reached.