Commercial Flush Valves

Commercial flush valves are tankless valves that connect to the water supply and release a measured volume of water to flush toilets and urinals. Also called flushometers, they use line pressure instead of a tank, which suits high-use restrooms in offices, schools, hospitals, stadiums, and other public buildings. 

This category covers commercial flush valves and components for water closets and urinals in commercial and institutional restrooms. In commercial toilet flush systems, the valve mounts to the supply line, holds back line pressure, and opens briefly to deliver a rated flush volume, measured in gallons per flush (gpf). After the flush, the valve closes and is ready for the next use without a refill cycle, so fixtures can flush back to back during peak traffic. 

Products here include complete valves for toilets and urinals, sensor and manual actuation options, and the internal parts used to service existing valves. Each valve is sized to the fixture it serves, so matching the gpf rating, spud connection, and supply line is the first step. For the fixtures themselves, see commercial toilets and urinals.

Product Group Explanation

Commercial Flush Valve Products

Products are organized by fixture type and actuation method. Each group below plays a specific role within commercial flush valve systems.

Closet Flush Valves

Closet flush valves are the commercial toilet flush valves used on wall-hung and floor-mounted bowls. They typically connect to a 1 inch supply and a 1-1/2 inch top or rear spud on the bowl. Common ratings include 1.28, 1.6, and 3.5 gpf, and the valve rating must match the bowl.

Urinal Flush Valves

Urinal flush valves deliver smaller flush volumes, commonly 0.125, 0.5, or 1.0 gpf. They typically connect to a 3/4 inch supply and a 3/4 inch spud. Low-consumption urinal valves reduce water use in busy restrooms when the urinal is rated for the same volume.

Flush Valve Parts and Repair

The flush valve parts and repair group covers diaphragm and piston kits, handle assemblies, vacuum breakers, control stops, and sensor modules. Replacing worn commercial flush valve parts restores a valve without cutting it out of the supply line, which keeps commercial flush valve repair to a single service visit.

Sensor Flush Valves

A sensor flush valve uses an infrared sensor to detect the user and trigger the flush automatically. Models run on batteries or hardwired power. Hands-free operation limits contact with fixtures, and sensor retrofit kits mount onto many compatible manual valve bodies.

Manual Flush Valves

A manual flush valve opens when the user moves the handle, with no power supply required. Manual models are simple to service and suit locations without electrical access. For accessible stalls, the handle belongs on the open side of the toilet.

How Commercial Flush Valves Work and Where They Install

How a Flushometer Works

A flushometer holds back line pressure with a diaphragm or piston seated over the outlet. Water in the upper chamber keeps it closed. Pressing the handle or triggering the sensor opens a relief valve, which vents the upper chamber. The diaphragm or piston lifts, water flows to the fixture, and a small bypass refills the upper chamber until the valve reseals.

Diaphragm and Piston Designs

Diaphragm valves use a flexible rubber diaphragm that flexes off the valve seat. Piston valves use a rigid piston and seal that move inside a sleeve. Repair kits are specific to each design and gpf rating, so identify the valve type before ordering parts.

Where Commercial Flush Valves Install

Commercial flushometers  in offices, schools, airports, stadiums, healthcare facilities, retail stores, and restaurants. These buildings have steady restroom traffic and supply lines sized for flushometer demand. Tankless fixtures also save space behind the bowl.

Key Specifications and Planning Steps

Flush Volume

Match the valve gpf to the fixture rating. Federal limits cap toilets at 1.6 gpf and urinals at 1.0 gpf, and many projects specify lower volumes.

Spud Position and Rough-In

Confirm whether the fixture has a top or rear spud, then measure the supply rough-in height and centerline before selecting a valve.

Supply Pressure and Line Size

Check the manufacturer's flowing pressure range. Closet valves typically use a 1 inch supply and urinal valves a 3/4 inch supply.

Exposed or Concealed Installation

Exposed valves mount on the finished wall for direct access. Concealed valves sit inside the wall behind an access panel.

ADA and WaterSense

Accessible flush controls must operate with one hand. WaterSense labels apply to toilets at 1.28 gpf or less and urinals at 0.5 gpf or less.

Choosing the Right Commercial Flush Valve

Start with the fixture: a toilet needs a closet valve and a urinal needs a urinal valve rated for its flush volume. For a commercial toilet flush valve replacement, record the existing brand, model, gpf, and spud position so the new valve lines up with the current piping. Choose sensor operation for busy, hands-free restrooms and manual operation where power is not available. Keep matching urinal parts and accessories on hand for routine service.

Frequently Asked Questions

Where can I buy commercial flush valves for toilets and urinals in the US?

Commercial flush valves are sold through plumbing supply distributors that stock commercial restroom products. This category groups closet flush valves, urinal flush valves, and flush valve parts and repair, so you can select a valve by fixture type and flush volume in one place.

What do I need to replace a commercial toilet flush valve on a top spud bowl at 1.28 gpf?

You need a closet flush valve rated at 1.28 gpf with a top spud connection, typically for a 1 inch supply. Before ordering a commercial toilet flush valve replacement, confirm the rough-in height and check that the valve includes the spud coupling, vacuum breaker, and control stop your installation needs.

Which is better for a high-traffic commercial restroom, a sensor flush valve or a manual flush valve?

A sensor flush valve suits high-traffic restrooms where hands-free operation and automatic flushing are priorities. A manual flush valve suits locations without power access and has fewer components to service. Both deliver the same rated gpf when matched to the fixture.

What is the difference between a diaphragm and a piston flushometer, and which is easier to maintain?

A diaphragm valve uses a flexible rubber diaphragm, while a piston valve uses a rigid piston and seal inside a sleeve. Both are serviced by replacing an internal kit. Maintenance depends on the model and supply water quality, so keep the matching kit for the installed design on hand.

What is the difference between a commercial flushometer and a residential toilet tank flush valve?

A residential flush valve sits inside a toilet tank and releases stored water through a flapper or seal. A flushometer has no tank. It mounts on the supply line and uses line pressure to deliver a measured flush directly to the bowl or urinal.

Why does my commercial toilet flush valve keep running after the flush?

A running valve usually points to a worn or dirty diaphragm or piston, a clogged bypass orifice, or a relief valve that is not seated. Close the control stop, open the valve, and clean or replace the internal kit with matching commercial flush valve parts.

How do I adjust the flush volume or water flow on a commercial flush valve?

Flow is adjusted at the control stop on the valve inlet. Open the stop until the fixture clears fully without splashing. Flush volume is set by the diaphragm or piston kit, so changing gpf requires a kit rated for that volume and a fixture rated to match.

My urinal flushometer gives a weak or short flush. What parts should I check first?

Check that the control stop is open enough for the fixture, then inspect the diaphragm or piston for wear and the bypass for debris. Confirm the installed kit gpf matches the urinal rating, since a low-volume kit on a higher-volume urinal produces a weak flush.

How do I tell what size and type of commercial flush valve I need for an existing toilet or urinal?

Identify the fixture type, its rated gpf (often marked on the fixture), the spud position (top or rear), and the supply size. Record the existing valve brand and model from the valve body or cover. These details determine the correct replacement valve.

What water pressure does a commercial flushometer need to flush properly?

Commercial flushometers depend on flowing line pressure. Each manufacturer publishes a minimum and maximum flowing pressure for its valves, and low-consumption models often need a higher minimum. Compare the published range with the building's measured flowing pressure before selecting a valve.

Do commercial flush valves need to be ADA compliant and WaterSense certified for a new commercial building?

Accessible restrooms require flush controls that operate with one hand and sit on the open side of the toilet, which sensor valves and properly placed manual valves meet. WaterSense is not a federal requirement, but many local codes, green building programs, and project specifications call for WaterSense labeled fixtures and valves.

What gpf flush valve should I use for a low-flow commercial toilet versus a urinal?

Low-flow commercial toilets typically use 1.28 or 1.1 gpf valves, with 1.6 gpf as the federal maximum. Urinals commonly use 0.5 or 0.125 gpf valves, with 1.0 gpf as the federal maximum. Always match the valve to the fixture rating.

Can I convert a manual commercial flush valve to a sensor-operated one without replacing the whole valve?

Yes, in many cases. Sensor retrofit kits replace the handle or cover on compatible manual valve bodies and add automatic activation. Confirm compatibility with the existing valve brand and model before ordering, and plan for battery or hardwired power.

How does a commercial toilet flush system work without a tank?

Commercial toilet flush systems use a flushometer mounted on a pressurized supply line. When activated, the valve opens for a set time, sends a measured volume of water to the bowl, then closes automatically using line pressure. No tank refill is needed between flushes.

What is the difference between an exposed and a concealed commercial flush valve installation?

An exposed valve mounts on the face of the finished wall, which keeps it easy to reach for commercial flush valve repair. A concealed valve is installed inside the wall with only the actuator visible, and it needs an access panel for service. Concealed installations are planned during rough-in.