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How to Adjust a Dual Flush Toilet Mechanism? – 5 Simple Steps!

How to Adjust a Dual Flush Toilet Mechanism
Written by Elizabeth Fincher
Last Update: August 10, 2023

Dual flush toilets are one of the latest innovations that has become an inseparable part of many of our daily lives. As the name suggests, dual flush toilets have 2 dedicated flush buttons. It takes way less water to flush liquid waste than solid waste.

Unlike regular toilets, dual flush toilets save water by using less water to flush liquid waste. Adjusting the dual flush toilet includes changing the level of the water and the flush push button.

If you need to adjust the mechanism of your dual flush toilet, a good understanding of who the mechanism works will make your job much easier, and that’s our target today. We’ll share how the mechanism works and how you can adjust the mechanism with minimal effort.

Let’s explore the working principle of a dual-flush mechanism and figure out how to adjust dual flush toilet mechanisms.

How Does a Dual Toilet Flush Work?

How Does a Dual Toilet Flush Work

The dual flush toilet comes with a button fixed above the tank -that allows you to get the quantity of water you would like to flush. The lower flush uses only about 3 liters of water to flush. However, the giant button uses about 5 liters.

This contraption, when compared with other or the older toilets that only use 5 gallons per flush for every flush, the dual toilet system boasts as an excellent choice for people who are cautious of their environment.

What’s more, we cannot underestimate how much you will be saving with a dual flush toilet.

How to Adjust a Dual Flush Toilet Mechanism: Step-By-Step

Step 1: Remove the dual flush toilet lid

In most dual flush toilets, the first thing to do is to unscrew the push on top of the cover; then, you can lift off the lid. When extracting go anticlockwise.

If you cannot remove it that way, or you notice that the button isn’t unscrewing, push down one of the pins as you remove the other pin from the bottom.

Now you can do the same thing for the other button after removing the button. Then you can unscrew the flush button assembly.

Step 2: Adjust the level

Adjusting the level of the water of the dual flush is simple. These toilets use a combined assembly float, which pushes up and down as dictated with water level controlling the flow of the water.

The ring-shaped contraption which fits over the valve by the left-hand side of the toilet is the float.

Based on the type of valve, there are two ways by which to adjust the water level. One of the route is through the screw sitting on top of the fill valve assembly.

Step 3: Tighten the screw

When the screw is tightened clockwise, the water level is lowered. However, when it is tightened anticlockwise, the float moves up, which raises the float higher, and this raises the water level.

The other way as to do with pressing both sides of the lock, which fixes the float valve on the fill valve line rail that is attached to the side.

Don’t be afraid when water fills the tank whenever you are trying to adjust the flush toilet. It is normal. The water shuts off when the water gets to the fixed level, when you are lowering the water level, and you are not going to see any changes until the toilet is flushed.

Step 4: Flush the toilet

Press down one of the buttons on top of the flush valve in the middle of the bathroom. Water gently exits the tank then refills.

Observe the new level, and if you have not gotten to the desired level, then you can adjust it. You can repeat this action as much as you like until you have gotten to your preferred level.

Step 5: Finishing

Do not forget the lid now that you are done adjusting the water level. Replace the lid. Just as you screwed in the dual flush, screw back the double flush line and peg the buttons back into its place, if it was removed. Do not also forget to adjust other dual flush toilets.

To conclude, the dual flush toilet is a handy system bound to save you money as well as giving you the satisfaction of contributing to conserving water.

Figuring out how to adjust dual flush mechanisms will give you more control over your water consumption. It’ll also keep the mechanism working for a long time.


Q. 1: How to change the dual flush level on the dual flush toilet?

Ans. The flush level is just the same as the flows put to flush. Adjusting the flush level is easy. Open the lid, once you get to the float, trace the assembly and tilt the valve on the left side to drop or raise the level of the water.

Q. 2: How does a dual flush toilet work?

Ans. The dual flush toilet is a useful contraption that gives a choice in the size of water to flush with, just as the name suggests, there are two choices. The lesser choice is preferred for liquid waste or easy flush while the other button, which is usually the lager button, should flush solid waste easily.

Q. 3: What are the different types of toilet flushing systems?

Ans. There are at least eight toilet flushing systems, they include:

  1. Tank fill valve
  2. Flapper flush valve
  3. Siphon flush
  4. Wash-down
  5. Pressure-assisted
  6. Gravity flush
  7. Double cyclone
  8. Dual flush

More and more flush systems are being innovated with the continual growth in modern science and technology.

Q. 4: What may cause my toilet to keep running after the flush?

Ans. There are a lot of reasons while the toilet will keep running after a flush. It might have a lot to do with a broken toilet, like a cracked flapper which when faulty will continue to let water drain down the toilet bowl.

About the author

Elizabeth Fincher

Elizabeth started her career as an interior design artist at a multinational interior design farm. She completed her masters degree from the University of North Texas back in 2010. She was also a Spelling Bee runner-up when she was 14. She took interest in bathroom interior designing after joining her first job. Later she started her own firm as an independent artist. She’s been one of the founding members of Toiletsguide. She examines the design and ergonomics of the units we review and directs the interior decoration team of our in-house research facility. Elizabeth plays piano masterfully and always finds time to entertain us in between our busy schedules.

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