As your friend who‘s fixed a running toilet or two, believe me when I say it‘s worth tackling a toilet that flushes but keeps on running. That constant sound of flowing water is more than just annoying – it can waste over 200 gallons per day and seriously drive up your water bill.
The good news? In most cases, the fix is an easy DIY project. This step-by-step guide will walk you through how to diagnose and repair a toilet that runs long after flushing. Armed with a little plumbing know-how, you can solve most toilet troubles and prevent hundreds of dollars in wasted water.
Why It Matters: The True Cost of a Running Toilet
Before diving into toilet components and repairs, it helps to understand what‘s at stake when you have a toilet that takes too long to stop running.
According to the EPA, toilets account for nearly 30% of household water use, more than washing machines, showers, or leaks. The average toilet uses about 3.5 gallons per flush, but models over 10 years old use up to 7 gallons.[1]
Now imagine if your toilet continues flowing for 5 minutes after each flush. That‘s over 40 additional gallons a day down the drain. Per the American Water Works Association (AWWA), the average family could end up paying $580 more per year on their water and sewer bill from a persistently running toilet.[2]
And that‘s not even considering possible leaks, flooding, and water damage if left unrepaired. Catching a running toilet early is crucial to avoiding exorbitant bills and expensive plumbing issues down the line!
Anatomy 101: Inside the Toilet Tank
To understand what makes a toilet run, you first need to know what‘s inside the tank:
- Flapper Valve – The rubber seal that lifts up when flushing to release water into the bowl. It then drops back down to seal the tank.
- Fill Valve – Responsible for refilling the tank with water after a flush. Shuts off at a preset level via the attached float.
- Float – This floating device connects to the fill valve and rises/drops with the tank water level. It controls fill shutoff.
- Flapper Chain – Connects the flapper to the flush lever, allowing you to manually lift the flapper to flush.
- Shutoff Valve – Allows you to shut off water supply to the toilet for repairs. Usually located on the wall behind the bowl.
Top Culprits Behind Toilets Running Too Long
Based on my experience, these are the most common offenders making your toilet run endlessly:
1. Worn Out Flapper
This humble rubber flap is the key to sealing water in the tank. But over time, it can warp, crack, or simply not make a tight seal. This allows water to continuously drip from the tank into the bowl, making the toilet run.
Fix: Replace the flapper. They‘re cheap ($5-10) and easy to swap out. Just be sure to read your toilet‘s make and model on the inner rim to match the correct size and shape.
2. Problem with the Fill Valve
Known more formally as the ballcock, this valve is supposed to stop refilling the tank when the water reaches an ideal level. If the float gets stuck, the valve doesn‘t close, or the assembly is adjusted wrong, it will overfill the tank.
Fix: Clean and adjust the fill valve float assembly and make sure the valve shuts off at the right level as marked inside the tank. Replace the entire fill valve if needed.
3. Vent Pipe Obstruction
Without air flowing in through the vent, drain water can siphon sluggishly out of the bowl, causing the toilet to run long.
Fix: Clear any clogs in the vent with a drain auger or snake. Detach and clean the toilet if needed to get full vent access.
4. Issues Around the Flush Valve
The flush valve at the base of the toilet can get clogged with mineral deposits and debris, preventing it from sealing properly after flushing.
Fix: Remove the toilet tank and inspect the flush valve seat for any buildup. Clean thoroughly or replace the seal around the valve.
Step-by-Step Guide to Fixing Common Causes
Once you‘ve diagnosed the issue, here are more detailed steps for resolving some of the most frequent toilet-running culprits:
Replacing the Flapper
- Shut off the water supply valve behind the toilet.
- Flush the toilet to drain the tank. Sponge out any remaining water.
- Disconnect the flapper chain from the flush lever arm.
- Remove the old flapper. Scrape the flush valve seat clean of any buildup with a plastic putty knife.
- Check the new flapper for correct size and shape per your toilet model.
- Put the new flapper in place over the flush valve seat. Apply gentle downward pressure to create a tight seal.
- Reconnect the flapper chain, allowing about 1/4 inch of slack.
- Turn the water supply back ON and allow the tank to refill.
- Flush the toilet a few times to verify the flapper seals and drops properly after each flush.
By following these steps, you can replace a faulty, leaky flapper in less than 15 minutes. But don‘t worry if it takes a bit longer your first try! Taking your time ensures you get a water-tight fit.
Adjusting the Fill Valve
- Check inside the tank for the water level indicator and shut off point marked by the manufacturer, usually around 1" below the overflow tube.
- Flush the toilet, then let the tank refill. Note where the water stops – this is your current fill height.
- Locate the float adjustment screw atop the fill valve. Give it a quarter turn counterclockwise.
- Let the tank refill again and check the new water level.
- Repeat steps 3-4, adjusting in quarter turns until the shutoff matches the recommended fill height.
Adjusting in small increments prevents overshooting and ensures you hone in on the proper refill level. This prevents the fill valve from adding too much water to the tank.
Replacing the Fill Valve
If adjusting doesn‘t solve the issue, the fill valve itself likely needs replacement. This involves:
- Shutting off the water and emptying the tank
- Disconnecting the water supply line
- Unscrewing the fill valve from the tank
- Swapping in the new valve and reattaching all lines
- Refilling the tank and adjusting the float as shown above
When installing the new valve, be sure to apply plumber‘s putty around the bottom to seal it to the tank. Tighten the lock nut securely.
Unclogging a Blocked Vent
From Above:
- Shine a flashlight into the vent pipe through the roof to check for any debris, nests, etc.
- Insert a drain snake into the vent and rotate to dislodge any obstructions.
- Use a chimney sweep brush attachment for extra scrubbing power.
- Flush the toilet to verify water drains quickly after unclogging.
From Below:
- Drain all water from the toilet bowl.
- Pour a few buckets of water rapidly into the bowl from shoulder height. Listen for gurgles from the vent pipe.
- If no gurgling, plunge the bowl vigorously 10-15 times. Then pour more water and listen again.
- If still no gurgling, use a closet auger in the bowl to snake the vent pipe.
- Consult a plumber if snaking fails – the toilet may need to be detached to access the vent.
With patience and the right tools, you can clear even the most clogged toilet vent pipe and get it flowing freely again.
When Should You Call a Professional?
As you can see, many common cases of toilets running too long can be resolved with easy DIY repairs. But don‘t hesitate to call in a pro if:
- You have an older or delicate toilet you‘re unsure how to service
- The toilet runs even after replacing the flapper and adjusting the fill valve
- You suspect the issue is with the toilet bowl or drain pipes
- Leaks are coming from around the base, indicating a problem with the wax seal
- You hear lots of gurgling or see bubbles, signaling vent blockage
- You don‘t feel comfortable shutting off water lines or disconnecting supply pipes
Though costs vary based on your location, you can expect to pay about $100 for a plumber to diagnose and fix a running toilet. In my view, that‘s money well spent for the convenience and peace of mind if you‘ve hit a dead end troubleshooting.
Answers to Common Toilet Running Questions
Let‘s round things out with some frequent questions about ongoing toilet troubles:
How much can a constantly running toilet increase my water bill?
If a toilet leaks at a rate of 0.5 gallons per minute, it can waste over 700 gallons per day. For the average family, this can mean an extra $400-500 per year in water and sewer charges according to AWWA estimates.[2]
What risks are there if I ignore the issue?
The constant flow of water can lead to flooding, leaks, water damage to floors and walls, mold growth, and erosion of pipes and plumbing components. The moisture and humidity can also warp cabinets, vanities, and drywall over time.
Why is my toilet running every 10 minutes for a minute or so?
This is likely due to a flapper that isn‘t fully sealing the tank, allowing water to slowly trickle into the bowl until the low water level triggers the fill valve to turn back on. Replacing the flapper should solve this common problem.
Can a running toilet overflow or cause flooding?
Yes, if the water reaches the top of the overflow pipe, it can start spilling onto the floor. In severe cases with a completely malfunctioning fill valve, the tank itself could overfill, crack, and flood the bathroom.
What causes the constant trickling into the bowl?
A trickling sound usually indicates a leaky flapper. Make sure it‘s properly sealed after flushing. Also check the chain – if it‘s too tight it can prevent the flapper from closing fully. Adjusting the chain is an easy fix.
In Summation…
I hope this guide has helped shed light on why your toilet keeps running and how to remedy some of the most common causes. The good news is that most running toilet issues can be resolved with easy, inexpensive repairs – no plumbing expertise required.
Just remember to work carefully, make adjustments in small increments, and don‘t be afraid to call in a professional if you encounter any problems. Catching and fixing a constantly running toilet quickly will save you headaches, money, and water damage down the road. Here‘s to happy flushing and lower water bills!
