Plumbing, Repairs

How to fix leaking toilet problems and save your money

how to fix leaking toilet

Our guide outlines how to fix leaking toilet problems without having to pay a plumber. Many of the leaking causes are quite simple to fix.

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Find more plumbing guides, tips and advice

A constantly leaking toilet cistern shouldn’t be ignored. Ten or more liters are lost every day due to a defective toilet flush. Depending on the damage, up to a hundred liters can disappear in the sewer. That drives the water costs up, so it will save money to know how to fix leaking toilet problems. Anyone who does not find a remedy here will receive a shock at the next bill in the form of a hefty additional payment for water usage!

Immediate measure: turn off the toilet inlet

So what should you do if the toilet keeps running and leaking? If you are in a home you own, shut off the water and look at what you need to do to fix the problem, following our steps for how to fix leaking toilet.

If you are renting, tenants should contact their landlord immediately so that the damage can be repaired quickly. Hiring the handyman is usually the homeowner’s job. If there is not only a trickle of water in the toilet, but there is a risk of greater wastage, the tenant should also shut off the water and only turn it on again when necessary.

The easiest way to turn off the water is to use the inlet to the cistern. This is often located as a corner valve in the inlet line of the box and can be turned off by hand. “In other cases the shut-off valve is in the water tank,” explains Pommer. Then the lid of the box must be removed. The valve, which is hidden under a cover screw, can then be closed with a screwdriver.

The landlord does not always pay the cost of repairing the toilet. Some rental contracts contain clauses that stipulate that minor repairs and maintenance work below a certain amount must be borne by the tenant. If there is such a provision in the contract, it can be an option for tenants to take action themselves. 

Surface-mounted and flush-mounted models

It is not difficult to repair a defective water tank yourself, either with surface-mounted or flush-mounted models. Both flushing systems look different, but work the same.

With the concealed model, the cistern is anchored in the wall or in a pre-wall installation. First of all, the decorative panel and the second panel underneath must be removed. If the boxes are installed above the toilet, the lid of the cistern can be pulled up.

Fix leaking toilet problems

how to fix leaking toilet

The cause of leaking toilet problems are usually soiled or worn seals, a jammed float or a broken valve. If the seal is defective, the shut-off valve must first be closed and the cistern emptied. Then you turn the cylinder in the box to the left or right to release it from its anchorage and unhook it. The gasket on the cylinder head is then cleaned with detergent or replaced. Before reinstalling, you should also clean the flush pipe opening with gel cleaner.

A failure of the water flushing can also be due to a broken inlet valve. If water constantly runs into the toilet bowl despite an intact seal, the inlet valve no longer closes properly. Then the water rises above the intended maximum level in the box and flows into the open standpipe and over the toilet bowl into the drain. Both valves must then be exchanged.

A defective float can also be to blame for excess water in the tank. The task of the float is to regulate the level of the liquid in the container. Older boxes often have a hard foam float that soaks up water over time. When this happens, it no longer rises high enough to close the valve. Sometimes the float also gets stuck, causing a constant flow of water. In such cases, the float can be made free again by moving or adjusting the linkage to the valve.

If a broken seal is the cause of the cistern leaking

The cause of the water loss is often a worn seal on the so-called lifting ball or bell or a flapper flush valve – the stopper that is lifted during the flushing process so that water flows. But the do-it-yourselfer can repair this themself.

1st step: Remove the cover from the cistern

Remove the lid of the cistern. You shouldn’t be put off by the somewhat confusing sight of the internal mechanics. Because basically it only consists of two elements, the aforementioned lifting bell and an inlet valve whose float regulates the water level.

Step 2: Empty the cistern and remove the lifting bell

You close the small corner valve, usually located on the side of the cistern, and thus shut off the water inlet. Now empty the cistern by pressing the flush button. If there is no more water, you hold the lifting bell as far down as possible with one hand, loosen its bayonet socket with a slight turn to the left and lift it upwards.

3rd step: Find the right seal

The ring-shaped seal is now exposed. After a few years of use, it will show cracks or limescale deposits. In such cases it is advisable to replace them. There are replacements in hardware stores, but unfortunately not in all cases. It is best to take the old seal, or rather the entire lifting bell, with you as a sample. But the toilet has to be flushed with a bucket until the new one is purchased.

4th step: Install a new seal

After replacing the seal, installation is carried out in reverse order. It is important that the bayonet lock engages securely and that no sensitive plastic part breaks.

5th step: Check the water level in the cistern

Once the cistern is open, the water level should be checked at the same time. To do this, open the corner valve on the side so that water can flow in again. If the water level stays below a marking line inside the container, everything is clear. If it rises above it, you can readjust a vertically attached adjusting screw on the float. Better to stay a few centimeters below the marking so that water can be saved in the long run.

Modern cistern design helps save water

In the case of very old cisterns, however, most of these repairs no longer pay off. New models are available quite cheaply, and replacing an old cistern with a modern model can reduce water consumption. However, care must be taken to ensure that the toilet and cabinet are technically compatible.

Toilets over ten years old usually need a cistern with nine liters. If these were combined with four or six liter flushing, blockages are possible. Many of the commercially available modern cisterns can also be set to nine liters.

gerhardt-richter Gerhardt Richter is a writer and a trainer at trade technical colleges, specializing in carpentry, plumbing, mechanics and construction.