How to fix a leaking concealed toilet cistern? Find out!

A leaking concealed cistern is a problem that not only irritates but can also lead to more serious damage in the bathroom. While it may seem that repairing such a unit is complicated, in reality most faults can be fixed yourself. Wondering how to do it? Below, we explain how to identify the causes of a leaking concealed cistern and how to carry out an effective repair. Be sure to read on!

Concealed cistern — what is it?

A concealed cistern is the system that triggers the flushing of water into the toilet bowl. Such a toilet cistern is hidden in the wall, so it isn’t visible at first glance. Thanks to this solution, the bathroom looks more aesthetically pleasing and the space is better used.

This system consists of a flushing mechanism mounted inside the wall, accessed through a service panel, usually located behind the flush plate. Although concealed cisterns are popular for their aesthetics and functionality, their repair may seem more complicated than traditional cisterns. Don’t worry, though!

Leaking cistern: causes

A leaking cistern in a concealed installation is a problem that can have several causes. The most common are:

• Dirt and deposits — limescale and other build-up can accumulate on parts of the cistern mechanism, making it harder for it to function correctly.
• Incorrect settings — sometimes the issue can stem from the mechanism being set incorrectly, which causes it to operate improperly.
• A damaged or sticking inlet valve — can cause a constant flow of water into the tank and an overflow.
• A damaged flush valve seal — the seal can wear out or crack, causing a leak into the toilet bowl.

How to fix a leaking concealed cistern?

This issue doesn’t always require calling a specialist. You can carry out the repair yourself by following the step-by-step guide below.

Step 1: Turn off the water supply

Before you start any work, turn off the water supply to the cistern. The valve is usually located near the toilet. This way you’ll protect yourself from flooding the bathroom.

Step 2: Open the service panel

Using a suitable tool, for example a screwdriver, open the service panel to access the cistern mechanism. Do this gently so as not to damage any components.

Step 3: Check the inlet valve

Inspect the condition of the inlet valve. If it’s damaged or shows visible signs of wear, replace it with a new one. Inlet valves are available in most plumbing supply shops — remember to choose a model that matches your existing fittings.

Step 4: Check the flush valve seal

Examine the flush valve seal. If it’s worn or cracked, replace it with a new one. Make sure the new seal is properly matched to your cistern model.

Step 5: Remove dirt and deposits

Remove any dirt and deposits from the parts of the cistern mechanism. You can use suitable cleaning agents or a soft cloth and white vinegar.

Step 6: Check the mechanism settings

Make sure the cistern mechanism is set correctly. Sometimes a slight adjustment is all it takes for the cistern to work properly.

Step 7: Testing

After completing the steps above, turn the water supply back on and test the cistern. Make sure the leak has been eliminated.

Leaking cistern: sort the problem and enjoy peace of mind

A leaking concealed cistern is a problem you can solve yourself if you know the basic causes and repair methods. It’s worth regularly checking the condition of the cistern and its components to avoid more serious faults and costly repairs. Remember, a well-functioning cistern means not only comfort but also savings in water and money. If the repair is beyond your abilities, contact a professional plumber who will resolve the problem quickly and effectively.