Dual Flush Retrofit Kits for Dual Flush Toilets – Do They Work?By
Sadly, no. This is one to file under, “Too Good to Be True.”
There are several aftermarket retrofit kits available today that promise to transform a standard toilet into a dual flush model that can “save more water than a high priced high-efficiency toilet.”
Unfortunately, these gadgets simply regulate the amount of water entering the bowl and do nothing to alter the water flow in or out of the bowl. Since bowl design is the most important factor in a toilet’s performance – and even more critical in low-flow toilets – these kits promise far more than they deliver.
As the Professor has previously explained, standard and dual flush toilets have different flushing mechanics. While standard toilets depend on siphonic action to “pull” waste out of the bowl, dual flush toilets rely on the “push” of water to clear the bowl. More advanced technology, such as the WaterSense-certified H2Option Dual Flush Toilet, combines the traditional siphonic “pull” force with the newer “push” action associated with the washdown flush.
Because standard toilet bowls are not specifically engineered for less water, homeowners will have as much luck using these retrofit kits as they would adding a brick to the toilet tank. Both strategies try to “trick” toilet science and will likely result in incomplete flushes. Worse, users will likely overcome this problem by – you guessed it – flushing again. Multiple flushes eliminate any possible water savings.
In addition to voiding the American Standard warranty on toilets, installing these types of gadgets will frustrate homeowners and discourage any future use of proven water saving technologies such as HETs and dual flush toilets.
Physics, as it turns out, is it right up there with “can’t fool Mother Nature.”