Why Your Toilet Keeps Running
Most often, a toilet keeps running because one of three cistern parts has failed: an inlet valve stuck open, a flush valve seal leaking into the pan, or a water level set past the overflow. This guide from the Brendale Same Day Plumbing team sorts the causes, the dye test, and the short list of parts a householder can legally touch. Every job we do is done by a licensed plumber.
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The sewage treatment plant sits on Brendale's river flats, so this suburb knows better than most where wasted water ends up. A cistern refilling around the clock quietly turns your meter for nothing. Find the fault early and the loss never reaches the account.
The Three Causes of a Running Toilet
Three parts cause nearly every running cistern: an inlet valve failing to shut, a flush valve seal worn enough to leak into the pan, and a level set past the overflow. Each one leaves a different sign behind.
The inlet valve refills the cistern after a flush and should stop once the float reaches the set level. Wear or a blockage in the inlet valve leaves the cistern filling slowly or never stopping at all.
The flush valve sits at the bottom and holds the water between flushes. Once the flush valve seal wears, water slips past into the pan and the inlet keeps replacing what is lost.
Each fault shows up differently:
- A constant hiss or trickle once the cistern has refilled points at the inlet valve.
- The cistern topping itself up when nobody has flushed, or water tracking down the pan's rear, points at the seal.
- Water running from the overflow, or the overflow pipe dripping outside, means the level sits too high and the inlet valve or float needs adjusting.
What Colour in the Bowl Tells You
Run the dye test: drop some food colouring into the cistern, leave the toilet alone without flushing, and any colour in the pan means the cistern is leaking. Unitywater publishes this check for householders hunting a hidden leak.
The steps take minutes:
- Lift the lid and put several drops of colouring into the cistern.
- Wait without flushing, then look into the pan for any colour.
- Flush to clear the colour once you have looked; the colouring will not stain ceramic.
Colour getting through with nothing flushed points at the flush valve seal. A clean pan means the flush valve is doing its job, so turn next to the inlet valve and the level.
Short on colouring? Tape dry toilet paper high on the rear of the pan, above the water line. Dry paper means no leak; damp paper means water is finding a way down the back.
Water Runs but the Cistern Stays Low
A cistern that will not fill usually comes down to three things: a worn inlet valve, a float sitting too low, or a stop tap left part-way. Start with the stop tap, the small valve on the line feeding the cistern, and make sure the supply is fully on.
The second pattern tells a different story. Water running in while the level stays put points to a flush valve seal draining the cistern as fast as the inlet valve refills it, and the level cannot rise until the seal is renewed.
The QBCC List of Unregulated Cistern Work
The QBCC lists three cistern parts as work outside licensing: a person with the right knowledge and skill can swap the drop valve washer, the float valve washer or the rubber suction cup. No licence, approval or report is needed for those three, though the finished work must still comply with the plumbing standards.
Every other toilet repair is minor work for a QBCC licensee, done without a permit or a Form 4. The QBCC licensed team at Brendale Same Day Plumbing handles all of it.
Rentals follow the tenancy Act instead: the owner or manager must keep the premises in good repair, and the tenant must report problems promptly. The Act's emergency list names a blocked or unusable toilet, not a cistern that trickles, so the fix counts as routine and the owner has a reasonable time once told.
What a Running Cistern Does to Your Water Bill
No, the concealed leak adjustment does not extend to water a cistern wastes. Unitywater excludes leaking taps, cisterns, hot water systems and other water appliances from that relief. Leaks and their losses sit with the property owner, who pays for whatever the cistern loses.
A dye test costs nothing. A toilet that keeps running does not.
When to Call a Plumber
Ring (07) 3523 7172 when colour shows in the pan, the hiss carries on after a refill, or the cistern will not fill at all. Our toilet repairs in Brendale service covers the licensed work beyond the QBCC's short list, from valve replacements to full cistern swaps.
Tenants should tell the owner or manager straight away, since the repair clock starts at that conversation. Owners can book the fix before the bill grows.
Running Toilet FAQs
Call (07) 3523 7172Why does my toilet keep running after flushing?
Usually the inlet valve is failing to close, a flush valve seal is passing water into the pan, or the level sits above the overflow. A hiss after the refill points at the valve, while a cistern topping itself up between flushes points at the seal.
Why is my toilet cistern not filling up?
The inlet valve is usually worn or blocked, the float sits too low, or the stop tap is left part-way. If water runs in but the level will not rise, the seal at the bottom is letting water straight out again. Brendale homes see all three faults.
Will food colouring stain my toilet bowl?
No, ceramic bowls come out unmarked, and a flush clears the colour away. Unitywater recommends this check for Brendale households hunting a leak, so use it freely.
What is the overflow in a cistern?
The overflow is a safety outlet that carries surplus water away before water spills on the floor. When the inlet valve stays open or the float is set too high, the level climbs and runs down that outlet.
Call Us to Stop the CisternWe'll call you back.
Book on (07) 3523 7172 for plumbing anywhere in Brendale. We're available 24/7, there's no extra charge for nights, weekends or public holidays, and every job comes with $0 call-out fees.
To claim your $0 call-out fee, call (07) 3523 7172 today.