A running toilet is more than just an annoyance—it can waste hundreds of gallons of water, drive up your water bill, and even lead to more serious plumbing issues if left unchecked. If you’ve noticed that your toilet keeps running long after you’ve flushed, you’re probably wondering what’s causing the problem and how to fix it. At Dyer Demand Plumbing, we’ve helped countless homeowners in San Jose and Santa Clara County diagnose and repair running toilets. In this article, we’ll explain the most common reasons why your toilet keeps running and what you can do to stop it.
How a Toilet Works
Before we dive into the causes of a running toilet, it’s helpful to understand how a toilet works. When you flush, the following happens:
- The flush lever lifts the flapper valve at the bottom of the tank, allowing water to rush into the bowl.
- The water in the bowl is forced through the trapway, carrying waste with it.
- As the tank empties, the flapper valve closes, and the fill valve refills the tank with water.
- Once the tank is full, the fill valve shuts off, and the toilet is ready for the next flush.
If any part of this process malfunctions, your toilet may keep running. Let’s explore the most common culprits.
Common Causes of a Running Toilet
1. A Faulty Flapper Valve
The flapper valve is a rubber or plastic component that sits at the bottom of the tank and seals the opening to the bowl. Over time, the flapper can wear out, become warped, or develop mineral deposits that prevent it from sealing properly. If the flapper doesn’t close completely, water will continue to leak into the bowl, causing the toilet to run.
How to Fix It
- Turn off the water supply to the toilet.
- Remove the old flapper and take it to the hardware store to find a matching replacement.
- Install the new flapper and turn the water supply back on.
2. A Misadjusted or Broken Fill Valve
The fill valve controls the water level in the tank. If it’s set too high, water can overflow into the overflow tube, causing the toilet to run continuously. Alternatively, the fill valve itself may be broken or worn out.
How to Fix It
- Check the water level in the tank. It should be about 1 inch below the top of the overflow tube.
- If the water level is too high, adjust the float on the fill valve to lower it.
- If the fill valve is broken, replace it with a new one.
3. A Worn-Out Float
The float is a small device that rises with the water level in the tank and tells the fill valve when to shut off. If the float is damaged or set incorrectly, it may not trigger the fill valve to stop, causing the toilet to run.
How to Fix It
- Inspect the float for cracks or damage. If it’s broken, replace it.
- Adjust the float to ensure it’s at the correct height (about 1 inch below the overflow tube).
4. A Leaking Overflow Tube
The overflow tube prevents the tank from overflowing by directing excess water into the bowl. If the water level is too high or the overflow tube is cracked, water can continuously flow into the tube, causing the toilet to run.
How to Fix It
- Check the water level and adjust the float if necessary.
- Inspect the overflow tube for cracks. If it’s damaged, you may need to replace the entire flush valve assembly.
5. Mineral Buildup in the Tank
Over time, minerals from hard water can build up in the tank and on the components, preventing them from functioning properly. This can lead to a running toilet.
How to Fix It
- Turn off the water supply and flush the toilet to empty the tank.
- Use a descaling solution or vinegar to clean the tank and components.
- Scrub away any mineral deposits with a brush.
6. A Cracked or Damaged Toilet Tank
In rare cases, a crack in the toilet tank can cause water to leak out, leading to a running toilet. This is a more serious issue that may require replacing the tank or the entire toilet.
How to Fix It
- Inspect the tank for cracks or damage.
- If you find a crack, contact a professional plumber to assess the situation and recommend the best course of action.
When to Call a Professional
While many running toilet issues can be fixed with a little DIY effort, there are times when it’s best to call in the experts. At Dyer Demand Plumbing, we recommend professional help if:
- You’re unable to identify the cause of the problem.
- The issue persists after you’ve tried to fix it.
- You’re uncomfortable working with plumbing components.
- You suspect a more serious issue, such as a cracked tank or a problem with your home’s water pressure.
Our team has the tools, knowledge, and experience to diagnose and repair running toilets quickly and effectively.
Why Choose Dyer Demand Plumbing?
At Dyer Demand Plumbing, we’re committed to providing top-notch plumbing services to homeowners in San Jose and Santa Clara County. Here’s why you can trust us with your running toilet issues:
- Licensed and Insured: Our team is fully licensed and insured for your peace of mind.
- Experienced Professionals: We’ve seen it all and know how to fix it.
- Transparent Pricing: We offer fair, upfront pricing with no hidden fees.
- 24/7 Emergency Service: We’re here when you need us, day or night.
Frequently Asked Questions About Running Toilets
1. Can a running toilet increase my water bill?
Yes, a running toilet can waste hundreds of gallons of water per day, significantly increasing your water bill.
2. How do I know if my flapper valve is bad?
If your toilet keeps running or you hear a constant trickling sound, the flapper valve may be the culprit. You can also add a few drops of food coloring to the tank and wait 15–20 minutes. If the color appears in the bowl, the flapper is leaking.
3. Is it safe to use chemical cleaners in my toilet tank?
Chemical cleaners can damage the components in your toilet tank. Stick to natural solutions like vinegar or consult a professional for cleaning.
4. How often should I replace toilet components?
Most toilet components, such as flappers and fill valves, last 5–10 years. Regular maintenance can help extend their lifespan.
Contact Us for Toilet Repairs
If your toilet keeps running and you’re not sure how to fix it, don’t let the problem go unchecked. Call Dyer Demand Plumbing at 408-826-7257 for expert toilet repair services in San Jose and Santa Clara County. We’ll diagnose the issue, provide a lasting solution, and help you save water and money. Let us take the hassle out of plumbing repairs—your toilet (and your wallet) will thank you!