We use the toilet cistern at least several times a day, so after a long period of use a malfunction may occur. A broken mechanism causes unnecessary water loss and thus increases the bill. Fortunately, repair of the cistern is not complicated and can be done quickly and efficiently.

How to repair a cistern? Before the cistern can be repaired, it is necessary to analyse the fault, find out its cause and determine where the water is leaking from. This will allow us to know what parts need to be bought and how advanced the repair will be. The defect can take various forms, and the most common ones are a cracked seal or a damaged valve.

How is the cistern built?

A traditional compact flush, which is available with a toilet bowl, is built in a very simple way and consists of two valves. One is used to supply water to the cistern and the other to flush the toilet bowl. The first valve is connected by an arm with a float.

When the vessel is filled, the float rises and thus closes the valve and water supply. The flush valve works when the flush button is pressed, which carries the valve and pours out the contents of the vessel. Protection against water spilling into the toilet is provided by the so-called bell, which closes the flush valve.

Cause of a leaking flush

To repair the flush, find the cause of the fault. Most often there are several situations. The flush valve becomes leaking and the cistern cannot fill completely. The filling valve leaks and thus water flows into the cistern all the time and then flows out through the emergency overflow. It may also be that the float is incorrectly adjusted or has broken off the valve. A defective seal, on the other hand, will make the cistern water seep into a thin stream, leaving an unsightly trickle of sludge on the toilet wall.

All these faults need to be repaired as soon as possible so that they do not cost us an additional water bill, a replacement of the toilet bowl or the whole cistern. Depending on the severity of the problem and our knowledge and ability to repair small household appliances, we can take care of the removal of the defect ourselves.

How to repair a leaking cistern when the filling valve is damaged?

Before starting any work on the cistern, it is necessary to turn off the valve with water and sometimes empty the vessel from water. Then unscrew the drain button and remove the cistern cover. To start with, check the position of the float, which is connected to the filling valve. When the float is at the right level, the water supply is automatically closed. If the float is positioned incorrectly, the water intake is incorrect.

The valve does not close completely, so water flows into the cistern all the time. Most often the fault is indicated by the sound of constantly flowing water. In such a situation it is necessary to set the float in the right position. It is best to adjust its height and check if the water stops flowing.

What to do if the flushing valve is broken?

If the flushing valve is the cause of the fault, it is usually a matter of a defective seal. A properly functioning valve is “closed”, and pressing a button makes the lock go away and the water outlet is open. This is where the gasket is located, which can break under operation. In such a situation, the water flows into the toilet bowl with a small jet. In order to replace the seal, it is necessary to turn off the water valve, remove the cistern cover and empty it completely.

The remaining water can be collected with a cloth or sponge. The seal does not have to be damaged, it could only slip or get dirty. First, clean it and place it in the correct place, and if this does not help, replace it with a new one. The second gasket, which is worth looking at, is located at the water inlet to the cistern.

How to repair a pre-wall installation cistern?

Access to a compact cistern is very easy, but how to repair a pre-wall installation cistern whose parts are hidden under the tile? The most common cause of a defect is the seal of the flush valve and the dirt that accumulates underneath it. This causes the water flush valve to not close. To replace or clean the gasket, the button and cover plate of the frame must be removed. The result is a small hole through which you have to do all the work.

This is the only difficulty, because the rest of the work is done similar to a compact flush. The mechanism inside is arranged differently, but its operation is the same. It’s worse if there’s a serious malfunction or the whole mechanism breaks down. Then the only solution will be to remove the tiles completely, break the plaster and replace the whole cistern.