Whether it is constantly gushing or there is a little trickle, a leaking toilet can do a lot of damage to your water bill. Don’t just ignore it. Read on to learn how to stop your toilet from running.

Step 1: First Checks

Running water usually means that there is a problem with your toilet tank. However, make sure to inspect around your toilet to check where else water may be leaking. You might have another issue contributing to the problem.

Also check that your flush button isn’t sticking, leaving your toilet on permanent flush.

Step 2: Turn Off Your Water and Remove Cistern Lid

Near the floor behind your toilet, there should be a shut-off valve. And just like any valve, go ‘righty-tighty’ until the water stops. It might be a little difficult, so if needed, use pliers or a lubricant spray.

Take off the cistern lid and give everything a good once over. If something looks obviously wrong, that is most likely where the issue is. Otherwise, you will have to inspect each part to find the problem. 

Step 3: Check the Flapper

A toilet flapper is a rubber seal between the toilet bowl and the cistern, found at the bottom of your cistern. If it looks grimy, give it a clean with a toothbrush, water, and vinegar. If it doesn't look too dirty, it won’t hurt to give it a clean anyway while you’re at it.

If it looks quite worn, brittle, warped or damaged, you will need to replace it.

Step 4: Check the Fill Valve and Overflow Tube

The fill valve is a long tube connected to the float ball that allows water to flow into the tank. A leak can cause it to constantly let water run through.

Unscrew it from its base. Give it a clean like you just did with the flapper and check for any damage. If it is damaged, take it with you when you buy a new one to make sure you have the right one.

The overflow tube is a vertical tube connection to the fill valve, usually in the middle of the cistern. Again, do some checks and replace it if needed.

Step 5: Check the Float

Turn your water back on at the shut-off valve.

A float ball or float cup indicates how high the water is in your tank. It shuts off the fill valve when water reaches the fill line. If the float level in your toilet cistern is set too high, water will keep flowing to the overflow tube, causing your toilet to continuously run.

First, check whether the float ball has a hole in it. Next, check it is at the right height. It should be between 2.5cm and 5cm below the overflow tube.

Connecting the fill valve and float is the float arm. There is an adjustment screw attached to the top of the fill valve. To lower the water height, adjust the screw to lower the float ball until it reaches your desired height.

Step 6: Check the Lift Rods and Float Arm

Both the lift rods and float arm should be straight to allow everything to work properly.

Adjust the lift rods connected to the flapper until it falls directly up and down. Adjust the float arm by bending it and making sure that the float doesn’t touch the side of the cistern.

What if the Problem Persists?

If you have done all the checks and cleaning in your toilet cistern and your toilet is still running, it is best to call a reliable professional plumber. There are a lot of parts to a toilet, and it can be confusing knowing where the problem is. Or the problem could be with the flushing system entirely! Learn more here.