Plumbing Tips

Why Does My Toilet Keep Running? | Bathroom Plumbing Brisbane

Why Does My Toilet Keep Running, and How Do I Fix It?

A toilet that won’t stop running isn’t just annoying — it can waste hundreds of litres of water a day and drive your water bill through the roof. Even worse, it may signal a plumbing fault that needs quick attention.

At A Grade Plumbing & Gas, we specialise in reliable, affordable bathroom plumbing across Brisbane, Ipswich, the Gold Coast and Sunshine Coast. Let’s explore why your toilet might be running, how you can fix it, and when to call in a licensed plumber Brisbane locals trust.

Common Reasons Your Toilet Keeps Running

  1. The Flush Valve Seal Isn’t Sealing Properly 

The flush valve seal is the rubber part at the base of your toilet’s cistern that lifts when you flush, allowing water to flow into the bowl. If this seal becomes worn, warped, or misaligned — or if the chain connected to it is too loose or too tight — water may continue to leak into the bowl, causing the tank to keep refilling.

  1. The Float Is Set Too High or Low 

The float controls how much water enters the tank. If it’s positioned too high, excess water flows into the overflow pipe and keeps the fill valve running. Too low, and the tank won’t fill enough for a strong flush.

  1. Faulty Fill Valve 

The fill valve (also called a ballcock) lets water into the tank. If it’s faulty or clogged with debris, it may not shut off when it should, causing ongoing water flow.

  1. Worn or Cracked Tank Parts 

Other components like gaskets and washers inside the cistern can degrade over time, especially in older toilets. This wear and tear can lead to leaks and pressure imbalances that result in constant running.

Quick Fixes You Can Try at Home

If you’re confident lifting the cistern lid and poking around inside, here are a few simple things to try before calling a professional:

Realign or Replace the Flush Valve Seal  

Take a look inside the cistern and observe the rubber seal during a flush. If it isn’t closing properly, adjust the length of the chain or consider replacing the seal entirely. You can find universal flush valve seal kits at most local hardware stores, and they’re typically easy to install.

Adjust the Float Arm or Cup

Depending on your toilet’s design, you may be able to adjust the float level with a screw or clip. Aim to have the water stop about 2.5cm below the top of the overflow pipe.

Clean or Replace the Fill Valve

If the fill valve is sticking or not sealing off fully, it may need a clean or complete replacement. Turn off the water supply before attempting this fix.

Do a Dye Test to Detect Leaks

Add a few drops of food colouring to the tank and wait 15–30 minutes without flushing. If coloured water appears in the bowl, you’ve got a leak — and it’s time for repairs.

When It’s Time to Call a Plumber

DIY fixes are great for small issues, but a toilet that keeps running despite your best efforts may indicate something more serious. Call a plumber in Brisbane if:

  • Water keeps running after multiple attempts to fix it
  • You hear hissing or dripping noises even when not in use
  • Your toilet flushes weakly or erratically
  • There are signs of water damage on nearby floors or walls
  • You suspect a hidden leak or worn-out pipes

A Grade Plumbing & Gas uses the latest in water leak detection technology to find and fix leaks fast — without tearing your bathroom apart. If the issue is urgent, our emergency plumber Brisbane team is available 24/7.

We Do More Than Just Toilet Repairs

Toilet problems often come hand-in-hand with other plumbing concerns. That’s why we offer a complete range of bathroom plumbing services, including:

  • Leaking tap repairs – Say goodbye to annoying drips and wasted water
  • Hot water repairs and installations – We fix and upgrade electric, gas and solar systems
  • Drain cleaning – Clear blocked toilets, sinks or showers quickly and safely
  • Emergency plumbing – Fast response when something goes wrong unexpectedly

Whether you’re dealing with a stubborn toilet or planning a full bathroom renovation, we’ve got the tools and experience to help.

Why Choose A Grade Plumbing & Gas?

✅ Licensed and experienced local plumbers
✅ Transparent, no-surprise pricing
✅ Prompt response across Brisbane, Gold Coast, Ipswich & Sunshine Coast
✅ Friendly, tidy and professional team
✅ Available 24/7 for urgent plumbing issues

We don’t just fix the problem — we get to the root of it, so it doesn’t come back.

Need expert help with a running toilet or bathroom plumbing issue?

Contact A Grade Plumbing & Gas today — your trusted Brisbane plumbers for fast, honest, and affordable service.