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How to Install a Dual Flush Conversion Retrofit Kit

I've had my own handyman business as a side job for the past few years and encounter a wide variety of home repair issues.

In this photo, you see that I chose to keep my toilet's original valve assembly and simply install only the dual flush valve and handle.

In this photo, you see that I chose to keep my toilet's original valve assembly and simply install only the dual flush valve and handle.

Save Thousands of Gallons of Water Every Year

Without changing how your toilet flushes in "regular" mode, a dual flush retrofit kit offers you the choice of not wasting a whole gallon and a half of water with each flush if you don't need to.

Dual flush toilets save thousands of gallons of water a year and reduce your water bills. Up until recently, you had to spend upwards of $300 for a new dual flush toilet. Now, several companies offer dual flush toilet conversion kits that are easy to install and achieve the same results as buying a new toilet. They work on almost any low-flush, 1.6-gallon toilet and turn it into a dual flush toilet.

Why Should You Use a Dual Flush Toilet?

Dual flush toilets have been common in water-scarce regions around the world for decades. In Australia, most toilets are dual flush. They feature two buttons, or two lever positions, one for solids and one for liquids.

Since we use the bathroom more often for "liquids" so to say, we don't need to flush all 1.6 gallons from a low-flush toilet down the drain. Instead, we can get by for small flushes with just half of that.

Imagine saving almost one gallon for those kinds of flushes, and you can see how quickly a dual flush conversion kit can pay for itself.

How Hard Is It to Convert Your Toilet to Dual Flush?

It takes someone with basic handyman skills about 20 minutes to convert a regular low-flush, 1.6-gallon toilet to dual flush. It involves removing the bolts that hold the tank onto the bowl, disconnecting the water line and taking the tank off. See below for complete details.

How Much Water Will a Dual Flush Retrofit Kit Save?

The best part is that a dual flush conversion kit will pay for itself in about two months at most city's water rates. Say, for example, you have a family of five and each person flushes for "liquids" about four times a day. That is 20 flushes wasting .8 gallons if you are not using a dual flush toilet.

Once you install the retrofit kit, the same 20 flushes will use 16 gallons less water. At 16 gallons a day, more than many families around the world use a week, you can expect to save almost 6,000 gallons of water a year.

Depending on where you live, that 6,000 gallons can cost you from $60–$300. There are not many green products that are so simple and inexpensive and yet pay you back so fast.

The Coming Water Crisis

It's front page news in many parts of the United States: "Water Shortage". Perhaps because of global warming or just population growth, water supplies around the country are being forced to require water rationing and increase rates for residential and commercial customers to curb demand. It will only get worse in the coming decade, so now might be a good time to start making your home more water efficient with products like a dual flush toilet.

How to Make Your Existing Toilet Dual Flush With a Conversion Kit

  1. First you must turn off the water supply to the toilet at the small valve down near the floor. For most toilets, you will need adjustable pliers and a number 2 Phillips or flathead screwdriver (depending on your toilet).
  2. Flush the toilet and sponge out any water that remains.
  3. Unscrew the water hose at the connection where it meets the tank. Next unscrew the wing nuts that hold the tank to the bowl. You may need your screwdriver to hold the screw heads inside the tank while you undo the wing nuts underneath the tank. Now the bowl should lift off easily. Carry it to your workbench and lie it on its side.
  4. Now you can unscrew the plastic nut on the part where the water leaves the tank and flows into the bowl. Most toilets have a large rubber piece that seals it to the bowl. Pull this off and unscrew the plastic nut that holds the flapper assembly or old toilet valve assembly in place.
  5. Place the flush assembly part of the new dual flush retrofit kit assembly in the tank, and make sure all the new rubber washers are in place as per the instructions. Screw it down snug but don't overdo it.
  6. Do the same with the valve part, which will connect to the water hose.
  7. Replace the old toilet flush handle with the one supplied.
  8. Now you can place the bowl back on the toilet, connect the small water line and you should be ready to turn on the water supply and fill the tank. Just make sure you have the large rubber washer in place between the tank and bowl.
  9. Now all you have to do is educate the family on when to lift up and when to push down to flush.
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Read More From Dengarden

New Dual Flush Converters That Don't Require Removing the Toilet Tank

There is now another type of dual flush conversion kit on the market that does not require taking the tank off.

It is called the MJSI HydroRight Dual Flush Converter. I installed one in less than five minutes. Both types are great water savers, but I must say that I much prefer a traditional handle to a push button. The EnviroFlush is an easier to use dual flush converter in my opinion.

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.


Martin Shard from Hai Phong, Vietnam on June 08, 2013:

I have done your way, it saves a lot of water, thanks to your sharing, I hope more people will do it this way

RunAbstract from USA on August 21, 2010:

I am so happy to learn about dual flush toilets, and conversion kits! We have been using the "if it's yellow let it mellow, if it's brown flush it down", method of "waste water conservation". But this sounds so much better! Thanks a bunch!

Money Glitch from Texas on April 29, 2010:

With more and more cities increasing their water rates this year; this will probably stay a popular hub for a while. Congrats again on your success. :)

Alfreta Sailor from Southern California on April 29, 2010:

I've been installing my toilets by myself for over four years now, but with the knowledge that I have I am leery of trying this. I'll have to hand this one over to a more experienced handy person. Thanks for this. Very good.

Pete Maida on May 31, 2009:

This is great! A dual flush toilet is almost unheard of in the states. With the approaching water crisis everyone should consider this. Thank you for this information; I'm going to consider this.

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