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How Do I Check A Leaking Toilet?

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To check toilet leaks it is important to know where and how to look. This will help with knowing exactly what to do to resolve the leaking toilet complication. Here at Optimised Plumbing Services, we know how to quickly check the toilet leaks and resolve them. Our Emergency Plumber team is here 24/7 to help Sydney inspect and repair leaking toilets. 

To best ways to check toilet leaks are:

  • Drop food colouring into the toilet, wait 20-30 minutes, and if there is still colouring present then there are leaks.
  • Inspect for puddles of water under the tank or bowl or internal leaks within the toilet fill valve.
  • Test the flapper by turning off the toilet water supply and wait 15-20 minutes. See if a decrease in the water level as if there is then the flapper is broken.
  • Inspect the water level through flushing the toilet and see if the float causes the water to stop.

Checking for Toilet Leaks

When it comes to toilet leaks they are simple to repair but can be difficult to pinpoint. Where the toilet leak is coming from and why it is happening can be difficult to inspect. To find where the leak is coming from can be simple though when knowing exactly what to do. There are three main methods when it comes to checking for toilet leaks.

Food Colouring or Dye

Food colouring is an affordable and easy way to determine where the toilet leak is. Any colour will work but red is recommended as it is the easiest to see.

  • Start by lifting off the tank lid of the toilet and setting it aside.
  • Flush the toilet and wait for the water to rise up to the water line within the tank.
  • Once the toilet has done a full flush, drop four to five drops of food colouring into the toilet tank. 
  • Place back the toilet lid to then wait around 20 to 30 minutes.
  • Once the time has gone by, inspect the inside of the toilet bowl. If there is clear water inside of the toilet bowl then a leak is not present. However, if the food colouring has entered the toilet bowl then this is an indication that there is a leak. 
  • It is recommended to do this with all of the toilets inside of the home or building. This is to determine if the issue is with one toilet of if it might be a joint problem. 

Water Level

Another way to check toilet leaks is to look at the water level inside the tank lid in seeing if the float is to blame. The float rises with the water to ensure that the inlet valve will know when to stop water flow. When the water goes past the overflow tube then the float might not work properly and causes leaks. 

  • Remove the tank lid of the toilet to then inspect the water level. When the water is above the overflow pipe then the float will need to be inspected. 
  • Inspecting the inlet valve needs the toilet to be flushed while the rod of the float is lifted. Hearing the water stop indicates that the float is responsible for the issue and will need replacing.


Flapper Valve

When the water does not go past the overflow tube but there are still noises or excess water flowing into the bowl then the flapper needs to be inspected. The flapper is what will stop water inside the tank going into the toilet bowl. 

  • Turn off the water supply valve which is close to the toilet. When this happens inspect if the water in the water tank decreases.
  • Wait 15 to 20 minutes to check the water level and is it has decreased. If it has then the flapper might be leaking or the chains are too tight.


Signs of a Leaking Toilet

The location of the leak can be a good indicator that the toilet needs repairs or replacing. To check toilet leak locations can be easy when knowing exactly where to look.


Under the Tank

Inspecting the water tank and for a puddle can help with knowing that the toilet is leaking. The rubber washers are usually to blame for a leak in this area which are located under the bolts. Touching under the tank and water is present can indicate that the bolts are not correctly tightened. Tightening the bolts can help stop this issue or replacing the washer might be the best option.


Around the Bowl

When there is water around the bowl of the toilet that this is often not a good sign. Also, if there are smells of sewage then this can also indicate that the toilet wax ring might need replacing. Often the wax ring is what will cause this issue when it is old and replacing it is the best option.

If the leak comes more from behind the toilet then the bowl might be cracker itself. Water drops will often be easily identifiable if this is the case and a cracker bowl needs to be replaced.  

If replacing the toilet is needed we recommend reading our blog ‘which type of toilet to install’ to know which models are suggested to be installed.


Reliable Toilet Leaking Experts

When the toilet is leaking or needs to be inspected for leaks Optimised Plumbing Services is the ones to contact. Our fully qualified plumbers check toilet leaks regularly and are the best at resolving the issues. Each plumber has the skill to work with all kinds and types of toilets and efficiently inspect for leaks. Regardless of the place, we work in our team will find toilet leaks and repair them professionally. 

Working across Sydney, we will check toilet leaks in the Northern Beaches, North Shore and everywhere else. We also offer expert Blocked Drain specialists who can work with blocked toilets and all other types of drainage

For professional plumbers to stop leaking toilets – contact Optimised Plumbing Services on 02 8074 1475 or email us at!

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