Plumbing, Repairs

How to fix a running toilet: 7 steps

How to fix a running toilet

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Clear guide on how to fix a running toilet outlines the common problems, immediate remedies and 7 steps for how to fix a toilet that runs.

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Everyone knows this situation: The water in the toilet runs and runs even though it has long since done its work. That can be expensive and has nothing to do with economical water consumption. Or the flush is difficult or impossible to operate. That can be really uncomfortable when you have to draw water from another tap with the bucket and pour it into the toilet, so it is worthwhile to know how to fix a running cistern or toilet.

In any case, the cistern needs to be repaired. But calling a specialist doesn’t necessarily have to be, because craftsmen are expensive. Cisterns consist of only a few parts and work according to comprehensible mechanisms. You can do it yourself. But you should bring a little calm and thought. Occasionally strange moves or unusual tools are recommended to trick things into order. You should refrain from doing that again.

The continuously running water is the most common problem with cisterns. Occasionally it also happens that the container only fills very slowly – a problem that may not require a repair very urgently, namely if you live alone in the household. On the other hand, something must be done immediately if the flush has no effect or is stiff or seized up, which is the first thing to look for in how to fix a toilet that runs continuously.

How to fix a running toilet: Descaling can be the solution

If you want, you can try to first pour a descaling agent into the cistern. Vinegar essence is an inexpensive means, but there are also special limescale cleaners. If you are lucky, only limescale was to blame for the problems, and these will be solved when the limescale is gone. If not, you can always take further action.

But it is also necessary to gain access to the cistern to fill in limescale solvents. This is easy when it comes to an attached cistern that has not disappeared into a wall or a porch element. The cover of a pre-plastered cistern can either simply be lifted up, or it is hooked in and then easily removed. If the cistern is in the wall, you can get to its interior by removing the push button and its cover. The cover is mostly attached and the button is screwed on.

A flashlight can be useful in finding the source of the problem, depending on the situation. It is recommended to first check the function of the lever and float. The lever between the button and the float can be detached or tilted, and the float can also be blocked. If limescale is the cause, the relevant parts are removed and then reinstalled after cleaning. Arrested and blocked components are brought back into the correct position. Proceed with caution, the plastic parts can break. If that has already happened, they have to be replaced.

How to fix a running toilet: Always replace seals

If the water runs when it shouldn’t, it may be due to defective or dirty seals. There is one at the inlet and one at the outlet. In most cases this is easy to see, in which case you unscrew the pipe connections and replace the seals. Since these seals are very inexpensive, they should be replaced if you are already working on the cistern. If you haven’t bought any new ones and the old seals are just dirty, they are decalcified and cleaned. You should also clean the pipe openings at the same time and make sure when screwing together that the threads are not tilted and really close tightly.

It goes without saying that you let the cistern run dry and shut off the inlet before replacing the seals. However, if you suspect that the two valves are defective, you have to refill the cistern with water. Then you watch what happens after the flush is activated: If water flows into the box, although it is already full, then the inlet valve is broken. If the outlet valve does not close even though the box is empty, there is either a problem with this valve or the float control is not working properly.

How to fix a running toilet: Do not use force

In this case one tries to adjust the float correctly, there is a screw that can be adjusted with a screwdriver. If it is on the valve, it is removed and cleaned. If the valve is damaged, a new one is needed. The screw threads are often stiff and tight, usually a suitable pair of pliers is needed. With this tool, all threads are tightened again after the parts have been replaced.

Whatever error you have fixed, it is definitely advisable to descale and clean all parts of the cistern – the greater the chance that you will not have to reach for the toolbox again soon. After the repair it is essential to ensure that all connections are really tight. With cisterns in the wall, water that penetrates into cavities in drops over months can cause serious damage. The cover plate is only reassembled once you have convinced yourself that the cistern is functioning properly.

Types of cisterns

In the cistern there is a mechanism and water that is used to flush the toilet. If you press the flush button, the mechanism is triggered and water is directed into the toilet. There is also a mechanism that controls the water level and is responsible for filling the tank. Each manufacturer has its own system, there are three different types:

  • Toilet with attached cistern
  • Wall mounted cistern
  • Cistern in pre-wall element or concealed

These three types can be opened in different ways. With the first two you can usually lift off the attached lid. However, if the cistern is in the wall and only the cover for the handle is visible, it must be removed. Behind it is the access to the cistern, usually behind a separate cover.

If the water continues to run in the cistern, there is no way around opening the tank and inspecting the interior. Here you should watch out for damage or limescale deposits, which can lead to malfunction. In many cases it is because the seal on the lifting bell is worn out. This is raised when flushing and the water can drain into the toilet. If the seal is defective, the mechanism may not work, the water from the cistern is constantly running or the cistern is not properly full.

The float has another important function in the cistern. This sits on the water surface, measures the fill level and closes the inlet valve as soon as the maximum water level is reached. Here, too, it is possible that the float is defective or has jammed. It can also be calcified or dirty, which limits functionality. In some cases, a light tap on the cistern can ensure that the swimmer can move freely again.

Important : A seal for the cistern or a defective or outdated float should be obtained from a hardware store before repairs. It is best to take the defective part with you. Spare parts don’t cost much. In addition, you should take a photo of the setup with your mobile phone in advance so that everything is back in place afterwards.

How to fix a running toilet: 7 steps

1. Open the cistern

If water runs out of the cistern, you should first open the cistern to investigate the cause. There are various options depending on the design. With older models that are placed on the toilet, you may have to use some force. In the case of a front-wall installation, you must first remove the push-button device, then the module plate. A screwdriver can also help pry it open.

2. Turn off the water

Before you get to work, you should turn off the water supply. The corresponding valve is located near the cistern. Then pull on the lifting bell to let the water flow out of the cistern. Now you can examine the inside of the box. This is where a flashlight can come in handy.

3. Clean or replace defective parts

Porous and thus permeable sealing rings on the lifting bell can now be removed and replaced with spare parts. You should take hold of the bell below and remove it from the bayonet socket by turning it to the left. Then you can remove the device and insert a new ring. Be sure to take a photo or sketch of the structure beforehand!

Tip : If water runs out of an old cistern, an old foam float may be attached. Since these can soak up, you should replace them with a new model made of styrofoam or plastic.

4. Descale the components

To decalcify the parts such as the lifting bell, float or the sieve from the supply line, carefully remove the parts. It is worth completely decalcifying all components. Carefully remove the sealing rings, if necessary with the pliers, as well as the strainer at the inlet. The parts are then placed in a bath of diluted vinegar essence, vinegar cleaner or descaler. The parts should lie in it for around two hours so that the lime dissolves. Stubborn calcifications can be removed with an old toothbrush.

5. Reinstall parts in the cistern

Now equip the cistern with the new components and sealing rings and reassemble. Pliers can also help here. However, one should work carefully so as not to damage the parts. With the help of the sketch or the photo, the components can be put back in place accordingly. The rotatable bayonet lock of the lifting bell should snap into place. Do not put the cover on yet.

6. Turn on the water and check the water level

Now open the water inlet again and let the tank fill up. The fill level should remain below the marking line in the tank. If it rises above it, you have to readjust the float. You can do this with a small adjusting screw that is attached to it.

7. Put on the cover and perform a test flush

Last but not least, you can put on the lid of the cistern and check whether the water is still running out of the tank. If all seals on the lifting bell and float have been replaced, everything should be fine again. However, if the water is still running out of the cistern, an expert should be consulted.