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Why won’t my toilet flush?

We may not like to shout about it, but most of us spend a fair amount of time in the bathroom and – for better or worse – that time is usually spent alone, in more or less quiet contemplation. Why not make the most of this guaranteed “me” time by turning your bathroom into a tiled temple of zen… and the toilet into a porcelain throne. Follow these seven tips to ensure you enjoy every bathroom break.

The beauty of the flushing toilet is in its simplicity. It is not a complex mechanism and when something is not functioning quite as it should be, you can probably fix it yourself without too much bother.

How a flushing toilet works

The modern flushing toilet has two core components, the cistern and the water trap (also known as the U-bend). The water trap seals your bathroom off from the rest of the toilet, preventing any smells or gasses coming up from the sewer below to which it is connected.The cistern is a water tank that collects a large amount of water and releases it very quickly through the water trap. The gravitational force of this large amount of water rushing through the toilet bowl pushes everything through the water trap and down into the sewer, then leaves a fresh body of water in the pipe, ready for the next visitor.The secret of a successful flushing mechanism is the fast delivery of large amounts of water into the toilet bowl. Anything that impedes this flow is likely to result in poor flushing performance.

Why is my toilet not flushing properly? – weak flush

If your toilet is not clearing the bowl when you flush, it is likely that either insufficient amounts of water are being released or that the water is being released too slowly. In either case, the first place to check is inside the cistern. Look at the water level. It should be sitting just below the overflow pipe once the toilet has finished refilling. If it is looking too low then it is easy to adjust. The inflow of water into the cistern is controlled by a valve connected to a float. The point at which this float stops the water inflow is adjustable (usually a screw or knob on the valve) and you will need to change this so that the float and arm can rise higher before the tap is turned off. If this doesn’t work then it may be that the float is punctured or the valve is broken. In either case, the relevant part would need to be replaced and you may want to seek the help of a professional.

Why is my toilet not flushing properly? – no or very poor flush

If your toilet is not really flushing at all then it’s likely that something has gone wrong with the very basic flushing mechanism inside your cistern. When you flush, the handle pushes on an arm with a chain on the end. This chain is connected to the flapper valve at the bottom of the tank, which is then lifted, letting the water out of the bottom. Once all the water is released, the flapper valve falls back into place and the weight of the new water flowing into the cistern as it refills, presses down and closes the valve again. If this process is not working it is because one of these core components is broken or maladjusted. If your handle is loose or not giving much feedback/resistance, then this could be the problem. Though a simple component, it is sometimes a bit of fiddle to get the handle set right and fully functional.

If it is not the contact between the handle and flushing mechanism that is at fault then the next thing to check is the chain. The chain inside your cistern may need adjusting. It should be fairly loose, but not too loose. Again, dependent on your model of toilet, this should be fairly easy to adjust. Lastly, you might need to replace the flapper valve itself. On rare occasions these can wear out or become brittle, not resealing the unit and letting it fill properly between flushes.

Why doesn’t my toilet stop running after I flush?

Perhaps less of a crisis, but still very annoying and wasteful, is the toilet that doesn’t stop running water. In by far the majority of cases this problem is caused by the water level being too high in the tank and therefore running continuously into the overflow pipe. This problem is usually caused by increased water pressure in the whole water system of your building. However, the issue can be simply solved by adjusting the position of the float arm on the valve, as outlined above (see Weak flush). In much rarer cases, the problem could be caused by a leaking flapper valve. In this case, you will just need to replace the flapper valve. Flapper valves are inexpensive and it’s a fairly simple job to replace them. Just turn off the water and flush to drain the tank completely. Then remove the old, worn-out flapper and replace it with a new one. If this is all a bit grimy for you there is also no shame in calling in a plumber for this job.

How to prevent toilet malfunction

Poor, non, or over flushing toilet? Don’t panic: often it’s easy to fix.

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