If you notice that your toilet is flushing very slowly, or if your flush is ineffective or even non-existent, don’t panic! A poorly flushing toilet is rarely the sign of major problems – instead, it’s more likely to be the result of a low water level in the cistern.
What’s the Correct Water Level?
There’s no set amount of water that a cistern should hold, as cisterns come in many different sizes. They typically range from a 4 litre capacity to a 14 litre capacity, although 9 litre cisterns are some of the most common in the UK. If you remove the lid of your cistern, you should be able to see the fill tube – a cylinder that sits in an upright position.
Ideally, your water level should be roughly half an inch from the top of the tube. This allows for water to easily enter the tube when the toilet is flushed, but prevents accidental trickles that can cause your toilet to keep re-filling. If you regularly hear the sound of trickling water coming from inside your toilet, it’s likely that the water level in your cistern is too high.
Adjusting the Float
Whether you’ve determined that your water level is too high or too low, there’s a simple solution – adjust the float. The float tells the cistern when to stop filling, so if it has become misaligned, it will stop the cistern filling too soon, or allow it to continue filling past the optimal point. The good news is that adjusting the float is much easier than it sounds.
The float will have a simple screw adjustment near to where it attaches to the rod. Tightening or loosening this screw will raise or lower the water level when the cistern fills. Although the direction you’ll need to turn the screw depends upon the type of float you have, you’ll typically find that it’s a clockwise turn to lower the water level, and an anti-clockwise turn to raise it. Always check the water level by flushing and allowing to refill before ticking ‘toilet’ off your to-do list!
If you’re keen to ‘go green’ and use less water in your home, there are a number of ways to conserve water in the bathroom, including lowering the water in your cistern. Water-saving devices that you simply pop into your cistern to raise the water level can reduce the amount of water you need by about one litre. Your toilet should flush well, and you’ll be doing your part for the environment!