Why Does Your Toilet Keep Running?

You press the flush handle, walk away, and still hear water running in the tank minutes later. That steady trickle wastes water every day and quietly adds to your bill. The fix almost always comes down to one worn or misadjusted part inside the tank.

If other plumbing issues pop up around the house, our plumbing services in San Jose can help you get ahead of bigger repairs. In this guide, Superior Plumbing & Drain Cleaning Services explains “Why does my toilet keep running?” and which part may be to blame for the issue.

How Your Toilet’s Tank Works

Every flush lifts the toilet flapper off the flush valve, sending water from the tank into the bowl. Once the tank empties, the flapper reseals the opening. The fill valve then refills the tank until the toilet float rises high enough to shut it off.

An overflow tube sits in the middle of the tank as a backup. If the float fails to close off the fill valve in time, extra water drains down this tube instead of spilling over the rim.

Common Causes of a Running Toilet

A handful of common problems show up again and again during service calls:

• Worn flapper: A cracked or warped flapper no longer seals properly, allowing water to leak into the bowl between flushes.
• Faulty fill valve: Sediment buildup can prevent the valve from shutting off, causing water to keep flowing into the tank.
• Float set too high: Water rises until it flows into the overflow tube instead of stopping at the proper level.

Each of these issues is common in older toilets and often causes a faint hissing sound or a slow trickle of water.

When To Call a Professional

Some fixes, like swapping a flapper or adjusting the float, are simple enough for most homeowners. Others point to bigger problems, such as a cracked overflow tube, a corroded water supply valve, or pressure issues further down the line.

Read more about common toilet problems if you want to troubleshoot further before calling for help. If you are still unsure why your toilet keeps running, a licensed plumber can take it from there.

Stop the Drip With Our Reliable Plumbing Services

Leaving a running toilet unfixed can waste hundreds of gallons of water and add real money to your bill each month. Our licensed technicians can usually spot the exact part causing the problem and get it repaired during one visit. For help with other issues around your home, check out the common plumbing problems we see most often in San Jose bathrooms and kitchens.

As a family-owned company serving the greater San Jose area since 2004, our team brings 35-plus years of combined plumbing experience to every job. Call Superior Plumbing & Drain Cleaning Services at (408) 709-7370 for answers to why your toilet keeps running. We’ll provide the most expedient fix so you can get back to enjoying your home again without worry as soon as possible.