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August 2020

3 Reasons why your toilet won’t flush and how to fix it

3 Reasons why your toilet won’t flush and how to fix it

Drain Doctor have been fixing toilets for over 25 years, so there is no need to feel down in the dumps if you start experiencing issues with your bathroom facilities.

Read on to find out our top three reasons why your toilet won’t flush and what you can do to fix it. However, if you don't have time to read on and need a 24-hour emergency plumber right now, get in touch! 

Before you carry out any work

Make sure you isolate your toilet’s water supply without turning off your whole mains, which is easy to do if you have a high-pressure isolation valve fitted.

To turn off the valve, simply turn the screw of the valve a quarter turn with a flat-headed screwdriver to isolate your toilet. Remember to switch the valve back on again once the work is completed.

Water levels are too low in the toilet cistern

Did you know that when you flush your toilet, you’re actually releasing water from the cistern into the bowl? This increase of water, in combination with the siphon, is what creates the suction needed to flush the toilet. This is why pouring a bucket of water down the toilet will force it to flush.

When there isn’t enough water in the cistern, you’ll likely get a weak flush or your toilet may not flush at all. We often find that an insufficient level of water is one of the biggest contributing factors to blockages as there is an insufficient volume of water to dispose of waste.

To fix this, make sure that the cistern water level is around one inch below the tank’s overflow tube. If it’s not, you’ll need to manually adjust the fill valve to change the level of water.

Using the adjustment screw on the ball valve will alter the height of the float rod and ball. Turning this screw anti-clockwise will increase the water level.

The flapper is damaged

The aptly named flapper can be found at the bottom of the toilet and ‘flaps’ open to release water from the cistern when the toilet is flushed.

In traditional-style toilets, this may be rubber and attached to a metal chain, while in siphon toilets this is a circular piece of plastic located within the siphon itself.

If the flapper is damaged, it won’t allow the toilet to hold water within the cistern, preventing the cistern from releasing the volume of water needed to generate a flush.

When this happens, the best thing to do is to replace a damaged flapper, since they are inexpensive and easy to replace. Remember to take your old flapper with you to your local plumbing materials supplier so that you can be sure you receive the correct size flapper for your toilet.

The toilet is blocked

If you notice that your toilet has a weak flush and the water levels in the bowl are higher than usual, you may be experiencing a blockage.

This can be caused by a number of reasons, including flushing too much toilet paper at once and flushing unsuitable items such as sanitary products, baby wipes or nappies which will all contribute to a blocked toilet.

The easiest and cheapest way to tackle a blockage is to use a plunger. In most cases, this will do the trick. However, the main issue with using a plunger is that it may push your blockage further up the pipe.

If this is the case, you may want to consider snaking the toilet using a toilet auger which you can purchase for as little as £12. These devices are similar to standard drain snakes but are specially designed to avoid scratching the porcelain of your toilet.

If all else fails, Drain Doctor are on hand to provide plumbing services across the UK. We offer 24/7 drainage support, where our skilled technicians use the latest advanced cleaning equipment to remove blockages efficiently and provide a long-lasting solution. To find out more about our services, contact our expert drainage technicians at Drain Doctor.