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BACKUP PREVENTION, SEPTIC
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BATH & KITCHEN DESIGN GUIDE
CHEMICAL CONTAMINANTS in WATER
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DEBRIS in WATER SUPPLY, Water Heater
DEPTH of SEPTIC TANK
DRAIN & SEWER PIPING
FAUCETS & CONTROLS, KITCHEN & BATH
FAUCETS, OUTDOOR HOSE BIBBS
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOOR DRAIN / TRAP ODORS
FLUSHOMETER VALVES for TOILETS URINALS
GAS PIPING, VALVES, CONTROLS
GALVANIC SCALE & METAL CORROSION
HARD WATER - SOFTENERS
HEAT TAPES, Heat, Insulation prevent Freeze-Up
LEAD POISONING HAZARDS GUIDE
LEAD IN DRINKING WATER, HOW to REDUCE
METHANE GAS SOURCES
MIXING / ANTI-SCALD VALVES
MUNICIPAL WATER PRESSURE IMPROVEMENTS
NOISE / SOUND DIAGNOSIS & CURE
ODORS GASES SMELLS, DIAGNOSIS & CURE
ODORS IN WATER
ODORS, SEPTIC or SEWER
ODORS SEWER GAS in COLD WEATHER
ODORS, SULPHUR SMELL SOURCES
ANIMAL or URINE ODOR SOURCE DETECTION
PIPING IN BUILDINGS, Clogs Leaks Types
PLUMBING FIXTURES, KITCHEN, BATH
PLUMBING NOISE CONTROL
PLUMBING VENT DEFINITIONS & CODES
PLUMBING VENT DEFECTS & NOISES
PUMPS, WATER REPAIR
RELIEF VALVE LEAKS
RELIEF VALVES - TP Valves on Boilers
RELIEF VALVES - STEAM TP VALVES
RELIEF VALVES - Water Heaters
RELIEF VALVES - Water Tanks
REPAIR BURST LEAKY PIPES
SEPTIC METHANE GAS
SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR
SHUTOFF VALVE LOCATION, USE
SULPHUR & SEWER GAS SMELL SOURCES
SWEATING (CONDENSATION) on PIPES, TANKS
TOILETS, INSPECT, INSTALL, REPAIR
WATER, WELLS, WATER TANKS: TESTING GUIDE
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PUMPS & TANKS
WATER SOFTENERS & CONDITIONERS
WATER SOURCE ALTERNATIVES
WATER SUPPLY & DRAIN PIPING
WATER SHUTOFF VALVE LOCATION, USE
WATER SHUTOFF VALVE, WELL PUMP
WATER TESTS, CONTAMINANTS, TREATMENT
WELLS CISTERNS & SPRINGS
WINTERIZE A BUILDING
This article describes the different types and models of toilets: historical or old toilet types, wooden high wall-tank toilets, conventional reservoir tank toilets, low-flush toilets, water saving toilets, back-flush toilets, up-flush toilets, and even chemical toilets. Here we explain how to diagnose and repair problems with toilets, leaks, flushes, odors, noises, running and wasted water.
Our page top photo shows ugly staining in a toilet bowl - strong evidence that this toilet has been running, wasting water, possibly flooding the septic system, and sometimes giving bad flush performance as well. This TOILET REPAIR GUIDE article series discusses the cause, diagnosis, and repair of toilet problems (water closet problems) such as a toilet that does not flush well, clogged toilets, slow-filling toilets, running toilets, loose wobbly toilets, and odors at leaky toilets.
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All modern toilets receive human waste, urine, feces, and are intended to dispose of that matter in a sanitary fashion.
By the late 1800's the development of the modern flush-toilet, replacing chamber pots and outhouses, toilets have relied on a dose of water to flush waste out of the toilet bowl into sewage piping or into a private septic system for wastewater treatment and disposal.
Take a look at the simple connection between a typical reservoir-tank toilet and the soil stack (waste piping) in the Carson Dunlop Associates sketch (left). This illustrates how most toilets are connected to a building drain. Back flush and up-flush toilets use a higher in-wall connection and are also explained in the article below.
Following this section of brief definitions of toilet parts & terms, these terms & key parts of toilets are illustrated and discussed in detail in the article below and/or in links or references we provide there.
Back-flush toilet: a back-flush toilet (illustrated and explained in the article below) is designed to flush horizontally out of the lower back of the bowl into a waste pipe that is mounted in the wall behind the unit. In comparison, a standard bottom-flush toilet is connected to a waste pipe in the floor below the unit. A traditional back-flush toilet is designed to work by gravity alone. Also see Up-Flush toilets, Rear-flush toilets, Toilets using a Sewage Ejector Pump, and Electric or pump operated toilets in these definitions.
Ball cock valve toilet fill valve: shown in our photo of a traditional side-float brass ball cock valve by Urrer, and in our sketch at below left left, the ball cock valve is the control that refills the toilet tank after a flush. the rod that carries the float, the float itself and other toilet parts are not shown in this illustration.
Toilet ball cock fill valve control designs include older tank-bottom sill-cock valves and modern anti-siphon valves (shown at left).
The diverter tube is clipped to the top of the toilet cistern tank overflow tube to deliver some water to the toilet bowl during tank refill.
The blue arrow indicates where the ball cock valve sends water into the toilet tank or cistern.
The float arm connector receives the float arm that carries the float ball assembly.
Ball cock valve adjustment: Most ball cock toilet fill valves have two screw or thumbscrew adjustments. One adjusts the angle of the float arm by moving the float arm connector position. The second adjusts the valve shut-off or closure point. Set both of these so that the water level in the toilet cistern or tank is at the "fill line" marked on the cistern body.
A modern anti-siphon sanitary ball cock valve places the water admitting assembly at the top of the valve while older units were "upside down", placing the admitting valve at the bottom of the toilet tank. A bottom-admitting ball-cock or other toilet fill valve is considered unsanitary by modern plumbing codes because in the event that the building loses water pressure, potentially unsanitary water can flow backwards from the toilet reservoir tank into the building water supply piping.
Bowl shapes of toilets: there are two basic toilet bowl profiles or shapes, round (which are not necessarily exactly round - illustrated at below left where a Church toilet seat is installed), and elongated or more of a flattened oval design (below right). Watch out when buying a replacement toilet seat, to be sure you select the proper seat profile (round or elongated) to fit your toilet, or you'll be making an extra trip back to the store.
In our photo my finger is pressing up on the lever that stops the flow of water into the toilet tank. You can see that an adjustable rod on the float (below the valve) will push up this stop lever on its own as the water level in the tank rises.
In some small-tank toilets we found that installing a concentric float toilet fill valve solved a problem of frequent jamming of the older side-float valve assembly whose float or rod would rub against the overflow tube or the toilet tank sides, jamming and giving recurrent "running toilet" problems.
Electric pump operated toilets make use of a pump to operate the toilet's flushing mechanism - that is, to clean the bowl. Traditionally an electric pump toilet has no reservoir tank - the flush water is delivered to the unit with sufficient force and volume by the electric pump. But some modern water saving toilets may employ an electric pump that adds water or air under pressure to improve the bowl cleaning action in the toilet while still using only a small volume of water.
Toilet Fill Valve: the toilet fill valve admits water into the toilet reservoir tank or cistern to refill the cistern following a toilet flush. Most fill valve designs also send some water through the overflow tube and into the toilet bowl during cistern re-fill. Two common fill valve designs in current use are the ball-cock toilet fill valve and the concentric float toilet fill valve. Both of those designs are illustrated above. Synonyms for toilet fill valves include: ball cock valve, concentric float valve, toilet water supply valve, toilet tank fill valve.
Float, toilet tank: the toilet tank float assembly activates the toilet fill valve as water level in the toilet tank or cistern drops during and at the end of a toilet flush. Illustrated above at concentric float toilet fill valves, the float for that device is a cylinder that moves down or up on a vertical shaft as tank (cistern) water level in the cistern falls or rises, to open or close the fill valve itself.
A ball cock toilet fill valve is opened by movement of a float arm rod attached to a round float ball (illustrated at left) that drops as water level in the cistern falls during a flush, and the ball cock valve is closed as the float rises, lifting the rod to which it is attached as the water level in the toilet tank rises to the fill line.
In our photo (above left) a white plastic ball cock fill valve is shown in lieu of the older traditional brass and bronze ball cock valve illustrated earlier on this page.
Toilet tank float adjustment: adjust the float lever angle so that combined with the ball cock shutoff adjustment the assembly stops water flow into the water tank when water reaches the fill line marked on the tank. If you do not see a fill line marked in the toilet cistern, set the fill level at least 1/4" below the top of the overflow tube. Also be sure that the float ball moves freely in the toilet tank. If the float ball rubs on the tank sides or end it is likely to jam and the toilet may not fill properly, or the toilet may run continuously.
Toilet Flush Valve: the toilet flush valve sends water out of the toilet tank or cistern (conventional flush valves) or directly from the building water supply without a toilet tank or cistern (flushometer valves) into the toilet bowl below to flush waste into the building drain system. The two most common toilet flush valves used on toilets that make use of a tank or cistern are the flapper type toilet flush valve (illustrated just below) and the tank ball type toilet flush valve (illustrated further below).
Flapper type toilet flush valve: (photo at left) (see below) is a toilet flush valve that closes the opening at the bottom of the toilet tank using a semi-round flapper (usually rubber) rather than the rounded tank ball shown in the sketch.
Like the toilet tank ball type flush valve (illustrated in the sketch below), the flapper valve is pulled up to open the toilet reservoir tank drain opening to send flush water down into the toilet.
The shape and position of the flapper cause it to remain in the open position until the water level in the toilet tank drops to nearly empty, then the flapper "flaps" down over the drain opening to stop the toilet flush cycle and to permit the toilet fill cycle to begin anew.
On modern tank type toilets we see mostly flapper valves; tank ball flush valves (below) are still found on older equipment however. Once the flapper valve is closed, water pressure from the filling toilet tank or cistern presses the valve face against the valve seat, holding it shut against leakage.
Toilet flush valve repair: If your toilet is "running" and has a flapper valve, often the leak between cistern and bowl is at this valve. Try cleaning the valve seat. If that doesn't work, a new flapper valve may cure the leak.
Other repairs include an epoxy add-on new flush valve seat that glues atop the existing one, or else disassembly of the toilet tank to replace the entire assembly.
If your toilet uses a tank ball flush valve, be sure that the lift rods move freely and are not bent or binding. The opening in the rod guide (see sketch at left) that guides the lift rod should be centered over the center of the tank ball.
Tank ball type flush valve: the control that sends water from the toilet tank (or building water supply) into the toilet bowl to flush away waste. There are many models of flush valves, using varying designs. A tank ball flush valve assembly is shown in the sketch at above left.
In a traditional side float flush valve assembly (sketch at left) the toilet is flushed by pressing on a handle outside the toilet tank that lifts a trip lever that pulls a chain or rod that lifts a tank ball or a tank flapper that otherwise seals the bottom of the toilet tank.
For modern toilets important are designs that conserve water either through the valve design itself (see Top Flush Control Toilets) or by means of a plastic "dam" around the valve assembly.
Flushometer or flush-o-meter toilet valves & toilets: these tankless toilets are flushed using building water pressure and a vacuum-breaker valve control. See FLUSHOMETER VALVES for TOILETS URINALS for details about these valves and how they are adjusted or repaired. Also see Toilet Types, Flush Methods for a discussion of variations in toilet flush mechanisms & methods.
Gravity flush toilet: (sketch at left) the conventional and most common water-operated toilet world-wide is flushed by water that flows (from a reservoir tank) into the toilet bowl by gravity; the reservoir tank must be above and is typically attached to or part of the toilet assembly, though early flush toilets (illustrated below) placed the flush tank much higher on the wall in an effort to obtain a more cleansing flush for early bowl designs.
When the toilet is "flushed" using its handle, a flush control valve (see "tank ball in our sketch above) opens to send water from the reservoir into the toilet bowl to flush it clean.
At the end of the toilet flush, a ball cock valve or equivalent (#1 & assembly "C" in our sketch at above-left) refills the toilet tank from the building cold water supply (the fat blue arrow in our sketch).
Hatbox toilet: a tankless toilet design by Kohler (illustrated below) that uses an electric pump to deliver flush water and adequate water velocity
Overflow tube, toilet: the overflow tube (item #8 in our sketch at left), is found on virtually all modern toilet flush control valve assemblies. This tube prevents a malfunctioning toilet tank refill assembly from flooding the building. (Unfortunately if the toilet drain is clogged and the toilet overflows you'll have a different sort of flood - see TOILET OVERFLOW EMERGENCY.)
During toilet tank re-fill, if the tank over-fills, the overflow tube (blue #7 in sketch at left) will excess water from the toilet reservoir tank down the overflow tube (#8) into the toilet bowl. This is a critical function since otherwise if the toilet fill-valve malfunctions water entering the toilet tank will fill the tank to overflowing and leak into the building. But if your toilet is "running" the problem may be just that - the fill valve is sending water continuously into the tank where it enters the overflow tube.
A second feature of most toilet fill valve assemblies and overflow tubes is that some water will be diverted from the fill valve into the overflow tube during the toilet tank fill-cycle - see the small curved blue tube marked #7 in our sketch above). This makes sure there is enough water in the toilet bowl before its next use.
Pressure-assist flush toilet: the toilet is flushed by water that is given a velocity boost by a pressure system using a pump,compressed, air, or other means. Typically pressure-assist toilet designs are found on water-saving low-flush-volume toilets.
Sewage Ejector Pumps combine an in-floor reservoir to receive waste from toilets (and often gray water as well), and a sewage grinder pump to lift wastewater to a building drain line that is higher than the plumbing fixtures served by the pump. Ejector pumps are often found in basement bathrooms in buildings whose sewer line exit above the height of the basement floor.
Siphon flush valve toilet: an alternative to the tank ball and flapper valve toilet flush mechanism used in the U.K. and in toilets in some other locales, toilet siphon flush valves are operated by a button that forces water up from the reservoir cistern (toilet tank) into the siphon that in turn sends water into the toilet bowl to complete the flush.
Siphon flush valve controls on toilets eliminate the problem of running toilets caused by leakage at the tank ball or flapper valve.
As you can see from our photo of an early toilet advertisement by Thomas Crapper & Cos. (from a wallpaper reproduction), the siphon flush valve is not a new idea, and has long been sold as a method of preventing water wastage and running toilets.
Squat toilet: squat toilets are a very old design still in widespread use in Asia and Europe. In most basic form (found by the author at the top of the Victor Emmanuel monument public restroom in Rome) the squat toilet includes a pan with islands for the user's feet that allow the user to straddle a hole in the pan center. In our Roman visit the author, answering nature's urgent call atop the Victor Emmanuel monument, was startled to find a cleaning person's mop suddenly appearing around his feet during use of that toilet.
A flushing mechanism for a squat may be absent, may use a nearby bucket and brush, or in modern squat toilets, a wall mounted cistern and flush valve as shown in our photo (Wikipedia ).
Depending on the era and locale of use, a squat toilet may empty into a modern plumbing and sewer system, or simply into a cesspool or in the 5th century and later, into a pipe that simply discharged waste to outside the building.
Toilet water storage tank (cistern): the water reservoir used to flush the toilet. On antique flush toilets (see the article below) the cistern was mounted several feet above the toilet and secured to the building wall.
Modern flush toilets that use a water storage have a tank bolted to the toilet bowl or incorporate a tank and bowl in a one-piece-toilet design.
Toilet Flange: a brass, plastic, or steel flange forming flat ring around and usually attached to the waste pipe in the floor or wall.
The toilet flange includes openings to permit the flange to be secured to the floor or wall as well as slots to accept the heads of toilet-mounting bolts that secure the toilet to the flange.
A toilet flange is shown in our photo at left (white plastic, below the yellow wax ring) and another toilet flange indicated by the red arrow in this photo.
Toilet mounting bolts secure the toilet to the toilet flange and in four-bolt toilets two more lag-bolts may secure the toilet to the floor itself.
Toilet rough-in dimensions locate the toilet waste pipe and flange assembly in the building rough and finished floor so that the toilet will be spaced a proper distance from the wall.
The toilet rough-in dimension illustration (left) shows the standard 12" distance to the waste line center from the finished wall and are illustrated by this adaptation from a Titan toilet package observed in Menards in Duluth MN. Toilets are installed
Details about how to install a toilet are at TOILET INSTALLATION PROCEDURE
Toilet rim heights: the height of the rim of the toilet bowl above the finished floor. To comply with the Americans with Disabilities Act (ADA) standards (16.5" to 18" above the floor) or ANSI 117.1a 2003 Safe Harbor standard (17" to 19" above the floor).
"Standard" toilets are a bit shorter, typically 14" to 16" above the floor surface. Add-on toilet rim height lifters are available that convert a standard toilet to ADA standards height. Note: ADA also requires grab bars and accessibility space for accessible bathrooms. See BATHROOM DESIGN, ACCESSIBLE for details.
Side-handle flush toilet: the most common toilet flush control uses a lever mounted on the toilet tank side or front near one corner to operate the flush valve. The lever typically lifts an arm that opens the flush valve.
Toilet Bolts: secure the toilet base to the floor or structure. Watch out: a poorly-secured toilet not only leaks into the floor, it is dangerous. A disabled person or anyone sitting down onto an insecure toilet can tip the unit over leading to serious injury.
Top-flush toilet or top-controls toilet: the flush operating control consists of one or more buttons or rods that project through the top of the toilet tank. Split top-flush controls permit alternative flush water volumes, typically using a 1.6 gpf flush for solid waste and 1.1 gpf flush for liquid-only waste.
Toilet supply shut-off valve: (blue arrow in our photo at left) a water shut-off valve installed below or close to water-operated toilets.
Up-flush toilets: an up-flush toilet is located below the building's sewer line and uses water pressure to move waste vertically to a drain line that is higher than the toilet itself. There may be some up-flush toilets with a built in electric pump but we have not found such; instead see Sewage Ejector Pumps above.
Water level in the toilet tank: most toilet tanks include a mark on the tank interior indicating the proper fill level for water in the reservoir tank. Adjust your toilet fill valve to fill to this level for proper flushing. Too little water may result in wasting water by having to flush the toilet multiple times.
Filling the toilet above the recommended fill-line wastes water at each flush and risks a "running toilet" if the fill level send water down the overflow tube. See the water level illustration above next to our definition of Gravity Flush Toilets.
Water-Saving toilets: use a lower total volume of water to flush or clean the toilet bowl, typically between 1.1 gallons per flush (gpf) and 1.6 gallons per flush. Synonyms: low water toilet, low water consumption toilet, low-flush toilet, high-efficiency toilet.
Water suppy valve, toilets: see Ball Cock Valve or toilet fill valve above.
Waterless toilets: any of a variety of toilet designs that do not rely on water to dispose of waste, including chemical toilets, composting toilets, outhouses, waterless toilets and other alternative toilet designs that are discussed separately at TOILET ALTERNATIVES. Also see Toilet Types, Design Choices where we describe the different toilet flush designs: gravity, power-assisted, and vacuum assisted flushing toilets.
Wax ring for toilets: a large wax seal placed between the bottom of the toilet and the upper surface of the flange or top edge of the waste drain pipe to which the toilet is connected. A wax ring is illustrated above at our discussion of Toilet Flange. Also see the toilet odor or toilet leak troubleshooting tips at Leaky Toilet Seals - Odors.
Chamber pots (dating from Roman times and Garderobes (5th to 15th century toilets that simply dumped waste to the outdoors) and privies and outhouses, toilet designs that date to the 1500s or earlier, see OUTHOUSES & LATRINES are omitted from this review of modern toilets. Here we also exclude squat toilets that are in wide use in both Europe and Asia.
By the 1880's, in London Thomas Crapper & Co's sanitary specialties included the elastic valve water closet illustrated at left, and the toilet cistern "water waste preventer" siphon toilet flush assembly design illustrated in the article above. The elastic valve closet advertisement at left (photo from a bathroom wallpaper reproduction) does not show the cistern or water reservoir tank.
By 1890 the elastic valve closet had been sophisticated and simplified in appearance to appear with a toilet tank or cistern mounted still higher on the building wall as we illustrate in our historic photograph (below left).
Mounting the cistern high on the wall gave additional water pressure that helped flush the toilet bowl clean. Subsequent toilet bowl designs have included many experiments & methods to improve toilet bowl cleaning, removal of solid waste without clogging, and to reduce "marking" - fecal stains on the toilet bowl surface that otherwise require a toilet brush and frequent cleaning.
Thomas Crapper & Co. (London) called their scary-looking toilet contraption an "Elastic Valve Closet".
Early flush toilets like the toilet shown in our photo (left, Locust Grove, - Samuel Morse Estate, Poughkeepsie, NY) and like this 1890 model used a high wall-mounted reservoir tank, typically wooden, to provide adequate pressure and flow rate to clean and empty the toilet bowl.
The flush valve for the wooden wall-mounted reservoir tank for this toilet was operated by pulling a chain that operated the mechanism.
Pulling the chain means flushing the toilet.
Bidet toilets & toilet seats
At left we include an illustration of the Japanese bidet toilet (. photo - Wikipedia). photographed in the Asahikawa grand hotel in Asahikawa, Japan. Bidet toilets deliver a warm water washing oscillating stream from beneath the seat (shown) that is adjustable in temperature and water spray volume. The toilets generally include a heated seat with a temperature control, warm air drying, and in some models massage and deodorizing features.
In normal operation the toilet won't send its oscillating spray into the air as the Wikipedia photographer achieved for this photo; the Toto bidet toilet seat includes a pressure sensor to prevent such accidents.
The Toto Washlet® toilet or similar bidet toilets are reported to be installed in 72% of Japanese households - a figure which we question considering the cost. Contact information for Toto is below in this article. This is a dual flush water-saving toilet.
The Toto B100 Washlet™® toilet seat is a retrofit heated and bidet-type washing mechanism that can be retrofitted to Toto (and possibly other) elongated bowl toilets. Particularly for the disabled, models of Toto's bidet toilets or toilet seats can be a significant benefit, as was the model installed by the author's sister. Also as an aid to the elderly or disabled are electric raised-seat toilets that provide a lift mechanism to assist the user in getting on and off of the toilet.
Contemporary Toilet Shapes, Sizes, Types, Designs
Contemporary gravity-flush toilets use a tank attached to the toilet bowl itself, relying on improved flush valve controls to provide the water flow rate into the bowl to empty it and clean the bowl sides. We illustrate several types below.
Below we illustrate a 1970's low profile toilet, a recent Canterbury™ one-piece toilet produced by Eljer (below center)that molds the toilet bowl and tank out of a single piece of material, and at below right we illustrate a contemporary Crane two piece 1.6 gallon flush toilet.
Among many modern designs for water saving toilets are shown below are the Glacier Bay top flush control dual flush two piece toilet (below-left) installed by the authors, a 1990's water saving toilet that uses a plastic reservoir baffle inside the toilet tank (below center) also installed by the author, and at below right is an Eljer Titan™ 1.6 gpf one piece toilet.
Tank reservoir toilets like the toilet in the sketch at left and in our photo just below, have been in wide use in North America since the 1940's.
While there have been improvements in toilet tank fill valves, flush valves, floats, and water savings, the design has remained about the same.
A flush lever moves an arm to lift a flapper valve or tank ball to permit water to rush into the toilet bowl below, washing away waste into the sewer pipe. [Other toilets may use a siphon-flush valve to activate the flush cycle.]
At the end of the flush cycle, a float arm, or a float moving on a vertical stalk (newer valves) drops to open a valve permitting the toilet tank to refill with water.
When the toilet tank water level reaches the proper level, the float closes the toilet tank fill valve.
More about the parts in the sketch are provided in the definitions at the start of this article.
Other contemporary low-water usage toilets such as this Thetford toilet model used in a manufactured home (doublewide trailer) combine a reservoir tank with high water pressure or a combination of air and water to flush waste from the toilet bowl while using a minimum of water.
At TOILET ALTERNATIVES we discuss low-water, no-water, chemical, composting, and incinerating toilets, listing models, sources, and characteristics of each model.
Top Flush Dual-Flush Control Toilets
Top-flush control toilets include both standard (typically a single rod is pulled or lifted - illustrated above) and water saving models (typically a pair of buttons giving different flush volumes) illustrated below. Dual-flush water saving toilets typically deliver 1.1 gallons to flush liquid waste or 1.6 gallons to flush solids.
The manufacturer gives a clue about which button provides more water (for solids), in this case by the number of raised bumps on the buttons of this dual flush water-saving model.
Below we give views of the dual flush mechanism for this toilet. The top buttons push vertical rods (we' ve flipped the toilet tank upside down) shown below-left. The individual rods push on different segments of the flush valve (below right) to send a smaller or larger of water into the bowl below.
For a low-profile toilet design that does not suffer from a weak flush, see the Electric Flush Toilets discussed below.
The water volume used in each toilet flush varies quite a bit, and flush volume will vary by flush type for dual flush toilets. Also the nominal flush volume for toilets may not accurately describe an individual toilet unit depending on how the toilet fill valve has been adjusted.
A back-flush toilet that does use a reservoir tank is also produced for special situations such as a location that prohibits installing a drain line in the floor below the toilet. At below left we illustrate a back-flush toilet installed in a Two Harbors Minnesota home.
Our second back-flush toilet photo (below right) shows a reservoir-tank back-flush toilet located in a basement in the Hudson Valley of New York. In this basement the sewer line ran just a few inches above the basement floor. The plumber mounted a back-flush toilet on a short concrete pedestal, raising it just enough to flush into the nearby sewer line found in the wall behind the toilet.
At left is a photo of a modern tankless, back-flush, flush valve operated toilet installed in Molde, Norway.
This toilet is also a back-flush model, sending waste out of the bowl towards the rear of the toilet and into a waste line in the building wall rather than in the floor.
The flush control for this tankless (cisternless) back-flush toilet is that round button just above the toilet tissue holder. Other water operated tankless toilets that are not back-flush models are discussed at Flushometer Toilets & Urinals.
Some modern brands of rear-flush toilets include American Standard, Burdett, Gerber, Kohler, Sani-Flow, Toto.
Our toilet photographs below illustrate a tankless, electric-flush toilet produced by Kohler. As you can see (below-left) the toilet may be a little unfamiliar to new visitors at the New Hampshire inn where this unit was installed.
Pressure-assisted flush toilets may use water pressure from the water mains to improve the flush cleansing of the bowl, or they may use a pump or an air bladder system that is in turn operated by water pressure. By providing a more aggressive and higher velocity flush than a gravity flush toilet a pressure-assist system generally uses less water, ranging from 1.1 to 1.4 gallons.
Kohler Purist Hatbox Toilets
For a newcomer, flushing this Kohler hatbox toilet could be a bit of a mystery. Searching for a flush lever or button finally leads to a round silver button located on the right side (if the user is seated) of the unit (photo, below right).
Pushing the flush button on the older unit that we tested produced an aggressive and roaring "flush" along with a bit of pump noise. Other literature describes these toilets as "quiet". Our photo at below left gives a clue about how this toilet was powered.
Newer versions of the electric flush toilet made by Kohler include a reservoir tank and an electric pump that moves water from the reservoir through the bowl and toilet trap. This design offers a toilet that provides a low profile but nonetheless a very powerful flush in a compact design.
The Kohler hatbox toilet installation we examined had been in place for some time; this product is still available at a typical retail price of $2,725.
Tankless flush-o-meter valve toilets, in widespread use in North America since the 1920's, and unlike tank reservoir toilets, do not include a reservoir tank of water. The flushometer valve is particularly suitable to public restrooms since there is no delay between toilet uses waiting for a reservoir tank to refill. Typical flush volume is 1.6 gallons.
Flush valve or flushometer type toilets rely instead on high water pressure, usually but not always from municipal water systems, along with a larger diameter water supply pipe, to clean the bowl and dispose of waste.
Invented by William Sloan in 1906, this valve type is still referred to as a "sloan valve" by some plumbers.
Unlike the electric flush toilets shown above a flushometer toilet or urinal relies on building water pressure and flow rate to clean the bowl and move waste past the trap into the building drain.
An auxiliary pump is not normally used.
Flushometer valves shown here are manual, operated by a push lever.
As most readers will have encountered, other flushometer valves are "touchless" and operate automatically after the fixture is used, relying on an infrared sensor to detect the presence or absence of a user.
See FLUSHOMETER VALVES for TOILETS URINALS for information about how flushometer valves work, are installed, adjusted, or repaired.
Flushometer Water Type & Waterless Urinals
A conventional flushometer valve water operated urinal is illustrated at below left. At right is a dry or waterless urinal.
An up-flush toilet relies on building water pressure to force the waste from the toilet up to a higher sewer line.
Because an up-flush toilet that relies on building water pressure to work forms a cross connection, these toilets are not permitted by plumbing codes in most jurisdictions.
In our photo of an up-flush toilet you can see the flush control lever mounted on the wall at the upper right.
Like the modern flush-valve toilet shown above, the up-flush toilet is also a back flush or rear-flush model. But don't confuse the two.
The flush valve toilet shown above does not form a cross-connection, drains into a gravity-sewer line rather than an elevated sewer line, and it is permitted by current plumbing codes.
Bathroom fixtures including toilets located in buildings whose sewer line exits high on the basement wall need a means to raise the graywater (sinks, tubs, showers, laundry) as well as blackwater or sewage from a toilet up to a height sufficient to drain into the sewer line and leave the building.
A residential sewage ejector pump is the most common solution to this need. The sewage ejector pump combines a small reservoir tank, a sewage grinder pump, and piping to grind and then pump sewage and wastewater from (usually) below floor level (such as in a basement) up to an elevated sewer line that then leaves the building.
Our photo (left) shows a typical basement installation of a sewage ejector pump. The toilet connected to this pump is not shown, but was located mounted on the floor nearby. A drain from the basement toilet was routed below the floor slab over to the black plastic holding tank shown in our photo. The white valve in the photo center, above the sewage pump's tank top, is a check valve to prevent wastewater from flowing backwards into the pump from above.
In a plumbing system using a sewage ejector pump, typically all of the plumbing fixtures (sink, tub, shower, laundry sink, clothes washer) drain under the building floor by gravity into the sewage ejector pump reservoir.
When the wastewater level in the ejector pump reservoir reaches a sufficient level, a float turns on the pump, forcing the wastewater past a check valve, upwards to the building sewer piping.
Depending on the arrangement of building piping, we sometimes find sewage ejector pumps that are located with the top of the unit a bit above floor level - possibly reducing the available storage volume between pump operation cycles.
Watch out: in the event of an electrical power failure, sewage grinders or sewage ejector pumps won't be working unless you have a backup electrical power source. So don't count on continued use of plumbing fixtures connected to one of these devices when there is no electricity.
Graywater ejector pumps: Also, don't confuse a sewage ejector pump with a graywater pump or lift pump that is sometimes found installed to move graywater from a basement laundry up to the building sewer drain.
For more detail about types of septic system pumps see SEWAGE EJECTOR / GRINDER PUMPS.
With more than 1000 brands of toilets manufactured and distributed around the world, this list would be endless. Here we list common or popular toilet manufacturers or brands. Contact Us to suggest changes or additions to this toilet brand list.
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Frequently Asked Questions (FAQs) about buying, installing, repairing, & maintaining all types of toilets