A running toilet will run up your water bill faster than you think. And there’s no reason to let this problem go so here are a few tips to correct those pesky leaks.

If you understand how a toilet works, it will eliminate the confusion about which part needs replacing. When you flush a toilet the rod connecting to the handle lifts the toilet flapper. On some toilets, it’s a ball and rod rather than a flapper. Either way, this action opens the drain at the bottom of the tank and the water drains out of the tank into the toilet bowl.

The force of the water flowing out of the tank directs the toilet flapper, or ball and rod, back into place. Inside the tank, there is a float that rises and falls with the water level in the tank. When the float lowers as the water goes down, it opens the water supply inlet valve. As water enters through the inlet valve, and the tank begins to refill, some water is directed through a tube into the overflow pipe and down into the bowl. When the tank fills with water, the float rises until it trips off the water supply inlet valve, completing the flush.

Many times it will be a matter of making a simple adjustment inside the tank in order for it to work properly. If the water never completely shuts off, check to see if the water level inside the tank is higher than the overflow pipe. If it is, adjusting the water level should fix it. Some tanks have a set screw on top of the water inlet valve where the arm of the float is connected. Turn it to adjust the water level.

Many people, however, find that bending the float rod down is simpler and just as effective a way of reducing the level of the water in the tank.

Some toilet fill valves have a spring adjustment clip on the rod connecting the canister-type float to the inlet valve. This clip can be moved up and down on the rod to adjust the water level. If the water level is not the problem, try putting several drops of food coloring into the tank. If within 5 to 10 minutes you see colored water in the bowl, the problem is that the water from the tank is constantly running into the toilet because the tank ball, or flapper, is not working properly.

If you have a tank ball, try adjusting the vertical rod that connects the tank ball to the flush handle rod. This rod is normally held upright by a plastic holder fastened around the overflow pipe. The rod must be perfectly perpendicular to the drain (also called the valve seat) of the tank in order for the tank ball to seal properly in the drain opening. If it’s not seated properly, water is escaping through the drain all the time. Adjust the rod if this seems to be the problem.

For toilets with flappers, the water may be running all the time because the flapper chain is so taut that there is not sufficient slack to allow the flapper to completely seat. Solve this problem by moving the “S” hook slightly higher on the chain. If the problem persists, you may need to replace the flapper or ball.