Know Before You Buy
Toilets - Dual-Flush

The federally mandated 1.6-gallon (6-liter) per flush toilets can save the average household up to 10,500 gallons per year for each toilet in use.
(depending on utility rates and usage habits)

But even these low-flush toilets use more water than necessary when flushing liquid wastes.

The average person flushes five times per day, and four of those are for liquids. The newest toilet innovation offers a choice of two water levels , one for each type of waste - sort of a combination urinal and toilet.

Dual-flush technology allows the use of 1.6-gpf/ 6-lpf (or less) of water to wash out solid waste but only .8-gpf/3-lpf to flush liquid waste.

The .8 gallon (3 liter) flush option, if used routinely to remove light or liquid waste, can save a household of four up to 6,000 gallons of water per year, per toilet, over traditional 1.6-gallon models.

Not only do these toilets save water, they are highly efficient. The 1.6-gallon setting will consistently remove bulk waste with just one flush, eliminating the potential for double flushing.

A recent study showed that dual-flush toilets can reduce the amount of water used in a single-family residence by 68%, in office bathrooms it was reduced by 56% and in restaurants it decreased by 52%.

For septic tank users, dual-flush toilets can reduce system loads up to 72%.

The Dual-Flush Difference
A dual-flush toilet looks like any other toilet, except that it doesn't have a flush lever. Instead, the user chooses one of two buttons, depending on the type of waste.

Some manufacturers place the actuator buttons on the top of the tank, and some on the side of the tank.

Because the technology is rather new, there are fewer design and color choices available on dual-flush models.

Dual-flush toilets are currently available in three different flushing mechanisms; washdown, washdown siphonic action, and power assisted.

Manufacturer's Suggested List Price for dual-flush toilets range from $230.00 to $1600.00, depending on the flushing mechanism.

  Washdown Dual-Flush
Perhaps the most efficient of the dual-flush models are those made by Caroma in Australia.

North American manufacturers produce toilets that use a siphonic flushing system. Siphonic toilets swirl water around the bowl to create a vacuum or siphon in the trapway, so water leaves the bowl first, pulling waste out afterward.

While this system works very well when large qualities of water are allowed, it is much more problematic when water is limited to 6 litres. To still be able to create the Siphonic action, trapways had to be reduced to generally around 2 inches. Naturally, the reduced trap size made clogging common.

Unlike North American toilets, wash down systems do not have to create a siphon in the trapway.

A steeper pitched bowl coupled with an open rim design pushes the water very quickly through the trapway, forcing the waste out first, followed by water. Because of the steep sides, only a small amount of water is required in the bowl.

Splashing during use isn't a problem and any staining of the walls is usually washed away in the flush. As with any toilet, an occasional scrubbing is necessary.

There are several advantages to wash down. Because they do not have to create a siphon, trapways are able to stay much larger. And the larger the trapway, the less likely the toilet will clog.

The Caroma has a 4-inch trapway- compared with the 2" industry standard. This innovation virtually eliminates clogging.

The Caroma flushes cleanly, in one flush, 95% of the time. Messy loads can sometimes require a second-flush to completely clean the bowl. In those cases a half-flush will finish the job.

The Buttons
The flush actuator buttons on the Caroma are located on the top of the tank. They are clearly marked for half and full flush.

How it Works
The Caroma is a gravity-fed toilet that uses a flapperless flush valve. When the half-flush button is pushed, only one side of the flush valve is opened. This allows only .8 of a gallon of water to be released.

When the full-flush button is pushed, both sides of the flush valve are opened, permitting the full 1.6 gpf.

Caroma is the only manufacturer that makes a button system for the visually impaired.

Larger Footprint
The base on all Caroma Australian toilets are approx. 20% larger than toilets produced in the USA.

Many times when changing out old toilets the floor covering will fall short around the base of the new toilet because all base footprints are different. Caroma solves this problem with their special floor connector.

The Toilet Seat
Most Caroma toilets come with an "Easy Clean Seat" that has a button on each side, by the hinges. Push in and the seat slides straight out and off. Caroma toilet seats can be safely cleaned in the dishwasher!

Prices / Maintenance
Caroma toilets are in the mid-price range - from $300.00 - $600.00.

Caroma makes euro-style, dual-flush toilets for both residential, ADA and commercial applications. Available in 10" and 12" rough-in. All U.S. models have a high tank profile and colors choices are limited to White & Biscuit. click here to see all Caroma models

Caravelle305

Reflections

Tasman

In addition to standard 10" and 12" rough-in models, Caroma makes a Walvit wall-hung bowl. The Water Wafer Inwall Tank can be fitted within a 4" cavity. A range of panel kits are available to suit dual flush and remote button operation. Water Wafer Induct Tank is suitable for behind the wall installations in a single service duct and is activated with the remote push button options.( Maximum distance from the buttons to the tank is 10' ). Models / Prices Caroma prices range from $300.00 to $800.00, depending on the model.

  Washdown Siphonic Action Dual-Flush
Sterling's Dual Force™ Technology combines benefits of both the Washdown and standard Siphonic Flush technologies.

How it Works


The flapperless valve and trapway design of these toilets maximize the force of gravity for remarkable one-flush, bulk operation. maximizes the force of gravity for exceptional on-flush, bulk operation. The durable valve system design ensures long-term operation and reliability.

The Buttons
The two-button actuator located on the tank top, provides easy-to-use flushing options.

Push the larger button on the left side for a full flush, and the smaller button on the right side for a half flush.

Models

Prices / Maintenance
The Sanitary Guard is a raised lip that supports the tank and helps prevent liquid from getting under the tank. The siphonic washdown system allows 100% of the water to pass through the rim, thoroughly cleaning the entire bowl.

Sterling's Dual Force™ technology can save an average family of four up to 6,000 gallons of water each year.

Sterling Dual Force™ toilets are in the mid-price range - from $235.00 - $340.00.

  Power Assist Dual-Flush
Kohler's approach to the dual-flush toilet uses Power Assisted - Power Lite™ technology.

How it Works
These toilets feature a .2-HP motor and pump that provide an extremely strong and uniform flush, regardless of incoming water pressure. (15 psi minimum)

Individually punched rim holes deliver a complete rim wash, without splashing. The 8.5" x 11" water surface helps keep the bowl clean and reduces odor.

The fully glazed trapway allows heavy wastes to move quickly with little blockage.

Generally, power assisted toilets use slightly more water when flushing liquid wastes (1.0-1.1 gallons) than do other flush technologies.

Power assisted require a 120 volt outlet protected by a Class A Ground Fault Interrupt (GFCI).

Please Note:
Due to the motor, power assisted toilets are noisier than conventional types. This dual-flush option can save an average household approximately 2,000 gallons of water each year.

 
The Buttons
 
Kohler's Twin Touch™ flush actuator has 2 depressions, the larger one for solid wastes, and the smaller for light or liquid wastes. The actuator is located on the side of the tank.

The Twin Touch™ flush actuator is available in a variety of metal finish options: Vibrant Polished Nickel, Vibrant Brushed Nickel, Vibrant Brushed Bronze and Vibrant Polished Brass.

Models / Prices
Kohler offers two, 12" rough-in, Power Lite®, dual flush models, both with a low profile, one-piece design and elongated bowl.

The Trocadero™ has all the elements of clean, European design.

 
The San Raphael™ is Kohler's lowest-profile tank.

It features a 2 1/8" trapway and uses 1.0-gpf (3.8-lpf) for liquid wastes and 1.4-gpf (5.3-lpf) for solid wastes.

Suggested List Prices begin at $925.60.
Price includes seat and cover. Available in 15 colors.

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