How to Fix a Running Toilet | Direct Energy Blog

How to Fix a Running Toilet

Welcome to the Take Charge of Your Home series from Direct Energy! Hiring a professional to perform household maintenance may offer convenience and peace of mind, but you can do many of these jobs yourself with no experience or special tools. And in the process, you’ll save money, learn about how your home works and gain a sense of accomplishment from a DIY task done well!

The flush toilet is one of the most essential conveniences of modern living, and yet it’s one of the simplest systems in your home. A toilet may go decades without professional plumbing service because maintenance and even some repairs are well within the abilities of the average homeowner.

Detecting and fixing a running toilet is one of the most common toilet problems you’ll face. It’s also one of the most wasteful — a running toilet can waste tens or even hundreds of gallons per day, which is bad for both the environment and your monthly water bill. Fortunately, it’s a job that requires no special tools, no formal plumbing training and no expensive parts.

How to Fix a Running Toilet | Direct Energy Blog

Is Your Toilet Running?

We’re not going to tell you to go out and catch it.

But after years of service, there are several reasons why an otherwise dependable toilet will start running. And that’s why it’s so important to know the signs of a running toilet and what you can do to fix it.

If your toilet is running, there’s a good chance you’ll hear the water flowing when it shouldn’t. You get to know a toilet after so many uses, and you know how long it takes for the tank to refill after a flush. If the hiss of that refill cycle is droning on and on, that’s cause for further investigation.

You might also catch visual evidence of a running toilet in the form of rippling around the edges of the water in the bowl. If your toilet hasn’t been flushed within the last minute, you shouldn’t be seeing this.

The worst-case scenario is discovering the evidence of a running toilet in the form of a spike in your water bill. This could be caused by a leak anywhere in your plumbing system, but your toilet tank should always be on the list of likely suspects.

If you’re in doubt, there’s a simple test you can use to diagnose a running toilet. Add a few drops of food coloring to the water in the tank, then wait a couple of hours without using or flushing the toilet. If the colored water shows up in the bowl, your toilet is running. If the colored water remains in the tank, it isn’t.

How to Fix a Running Toilet | Direct Energy Blog

The Anatomy of a Toilet Tank

Running toilets are so easy to fix because there are only six simple, easily accessible parts under the lid of your toilet tank.

Flush handle assembly: this includes the flush handle on the outside of your toilet and an arm that extends into the tank, connecting to the flush chain.
Flush chain: a length-adjustable chain extending from the flush handle arm to the flapper.
Flapper: a rubber stopper at the bottom of the tank that separates the water in the tank from the water in the bowl.
Overflow tube: a vertical plastic tube with an open top to drain water from the tank, preventing overflow.
Fill valve: a pump assembly that refills the tank after every flush and connects to the float arm.
Float: usually a rubber ball at the end of a float arm, this component tells the fill valve to stop pumping water when the tank is full.

One More Thing

There’s one more important component: your toilet tank’s shutoff valve. This is usually a hand-crank knob extending from the wall behind the toilet, with a water line leading into the toilet tank.

To complete most diagnostic and repair tasks inside the tank, the tank will have to be empty, which means the shutoff valve will need to be closed. And if you’ve never closed your toilet shutoff valve before, you might find that it’s stuck open due to accumulated mineral deposits or rust.

In extreme cases, these bonds can be so strong that the shutoff valve will need to be replaced entirely. When the sticking is less severe, an application of penetrating oil may get things moving. But if you find yourself in the position of having to force a toilet valve closed, the wise move is to close your household plumbing’s main shutoff valve first. That way, if you accidentally damage the valve, you won’t flood your bathroom.

How to Fix a Running Toilet | Direct Energy Blog

A Slight Adjustment

One potential cause of a running toilet should be apparent as soon as you lift the lid on the tank. If the water is continuously draining down the overflow tube, that means the float is positioned too high. The ideal position is about an inch below the top of the tube.

In some toilets, the float arm is made of flexible metal and can just be bent downward like a coat hanger. But most flush assemblies have a screw or knob that you can use to adjust the arm where it connects to the fill valve. Tinker with this until the water level is appropriately set just below the top of the overflow tube.

Flapper Time

If nothing is going down the overflow tube, the next thing to check is the flapper. Typically made of rubber, flappers can become brittle and cracked after years of use, which can allow water to seep from the tank into the bowl. They can also become coated with mineral sediment from your water, which can inhibit a tight seal.

To test your flapper, reach into the tank (don’t worry; the water is clean) and gently push it down. If that stops the toilet from running, the flapper is the problem. Remove the flapper from its hinges and examine it closely — if it’s coated in sediment, clean it and replace it to see if that solves the problem. If it’s cracked and damaged, replace it. Take the old one with you to the hardware store to find a match that will perfectly fit the flapper hinges in your toilet tank.

Check the Chain

When it comes to the chain connecting the flush handle to the flapper, length matters. If it’s too short, the flapper could be held slightly open all the time, causing the toilet to run. Too long, and you’ll have a loose flush handle and run the risk of the chain getting caught beneath the flapper. You want about three or four links worth of slack on the chain when the flush handle is at rest.

Most flush chains are adjustable via the use of a removable clip that attaches to the flush arm. Move this clip up or down as needed and re-attach it to get the right length.

The Last Resort

If you rule out the float, the flapper and the chain, the only remaining culprit is the fill valve. Fortunately, replacement fill valves are generally one-size-fits-all and available for less than $20 at any hardware store.

To replace a fill valve, you’ll need to use a wrench to completely disconnect the water line leading into the toilet tank. This will open up a hole in the bottom of the tank, so use a towel to soak up any water that remains in the tank before disconnecting the line.

Your new fill valve will come with installation instructions, but the process is generally as easy as lifting out the disconnected valve, inserting the new valve and reconnecting the water line.

From DIY to H-E-L-P

Fixing a running toilet isn’t rocket science. If your toilet is running, one of these repair steps will solve the problem. But when your toilet troubles get more complex, calling upon your licensed, local plumbers is the safest way to ensure the job gets done right.

About 

Josh Crank is a freelance writer and content marketer with a background in legal journalism, travel writing, and marketing for numerous commercial industries. He's found his perfect fit at Direct Energy in writing about home maintenance and repairs, energy efficiency, and smart home technology. Josh lives with his wife, toddler son and endlessly howling beagle-basset hound mix in New Orleans.