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Why It's Important to Fix That Running Toilet


Leaking toilets are more than just an annoyance—they waste water which leads to higher water bills. The next time you hear the unmistakable sound of a running toilet, it's a sign of a leak in need of immediate repair. The good news is that sometimes diagnosing and fixing the issue can be a simple and inexpensive task.

The Costs of a Running Toilet

According to the United States Geological Survey, a leaking toilet that is allowed to run continuously can waste up to 22 gallons of water a day. If allowed to run a full year, that's a leak that amounts to over 8,000 gallons of water. The impact is multiplied for each leaking toilet in your facility.

Now consider how that shows up in water bills. While utility rates and rate structures vary across the country, household water and wastewater bills are up more than 4% annually for the last nine years through 2021, according to Bluefield Research.

Common Causes of Leaks

Most toilet designs share a few common components and failures in any one of them can cause a leak.

Failing Valves: Toilets generally use two types of valves to function: a flush valve to control the flow of water into the bowl when the toilet is flushed and a fill valve to control the filling of the tank if a toilet includes one. Both valve types contain seals that can become warped or damaged over time and allow water to constantly “run” into the tank or bowl. These valve seals can be replaced individually or as part of an entire valve retrofit/replacement kit.

Broken Components: The flushing and filling valves in a toilet are typically controlled by mechanical components like flappers with attached chains and float rods. Wear and tear in these components can cause valves or seals to not fully close. Metal components can rust and simply fall apart over time. One should ensure that each component is installed properly and aligned correctly in the tank to prevent leaks.

Loose Handles: Over time the toilet’s flush handle can become loose or break-off completely and allow water to continually flow into the tank or bowl between flushes. Loose handles may be caused by an overly tight or loose chain or a bad mounting nut. It may be necessary to adjust or replace the flush handle entirely if it is causing a leak.

Faulty Sensors: As “touchless," sensor-operated toilets become more popular there is an increasing need to inspect and repair the automated flushing components. These include the sensor “eyes," power supplies and the connection wiring. Faulty sensors can force toilets to flush multiple times even when no one is around.

How to Fix a Leaking Toilet

Before going to the trouble and expense of hiring a professional plumber, there are some steps you can take to diagnose and repair a leaking toilet. If after looking into these potential problems you still have a leak it may be necessary to replace the toilet altogether and/or hire a plumber.

  1. Ensure you have a leak. According to the Portland Water Bureau, you can see signs of a leak if streaks of mineral buildup form on the walls of the toilet, if water continues to run into the bowl after a flush or if the water level in the bowl constantly changes.
  2. Inspect the valves. According to FacilitiesNet, an improperly sealed valve or one that does not close fully after flushing will leak water constantly. Commercial flush valves may make it difficult to detect a leak but they can be opened and inspected for failing valves or broken components. Valves can be replaced individually or as part of a kit.
  3. Inspect the flushing mechanism and handle. Broken or rusted components in the flushing mechanism can cause a leak. According to FacilitiesNet, cleaning or replacing flush handles can resolve many issues, while replacing old O-rings that connect the flush assembly to the toilet can help prevent leaks.
    Leaking toilets can waste thousands of gallons of water and increase water bills. Repair or replacement of flush valves, fill valves and flushing mechanisms and handles can address most leaks.

Learn more about Grainger’s plumbing supplies and hardware and other water-saving changes you can make across your facility.


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The information contained in this article is intended for general information purposes only and is based on information available as of the initial date of publication. No representation is made that the information or references are complete or remain current. This article is not a substitute for review of current applicable government regulations, industry standards, or other standards specific to your business and/or activities and should not be construed as legal advice or opinion. Readers with specific questions should refer to the applicable standards or consult with an attorney.