Over the years, different toilet fill valve types have been used in plumbing systems. Understanding the evolution and differences is key, whether you are installing a new toilet or replacing an old toilet fill valve.
Toilet Fill Valve Types You Need to Know
Each type features unique characteristics, such as water efficiency, anti-siphon protection, and the method of installation. I will dive into the specifics of each type, including their mechanisms, durability, and suitability for different toilet designs.
1. Float-Cup Fill Valve
The float-cup fill valve, introduced by Fluidmaster in the 1950s, is still the most common type of fill valve found in homes. As an industry standard, they are known for their compact design and reliability.
The cup-shaped float has a plastic body and a floating O-shaped cup. The anti-siphon fill valve rises and falls with the water level in the tank. When the handle is turned, the water increases, and the cup lifts a metal actuating rod that opens the supply valve and allows water to flow into the tank.
The anti-siphon toilet valve is attached with a metal spring clipped to the rod. When the water reaches the top of the fill valve shaft, the floating cup closes the supply valve and shuts off the water flow.
2. Diaphragm-Type Ballcock Fill Valve
Usually found in older models, the diaphragm fill valve is similar to the float-cup fill valve but uses a rubber diaphragm instead of a float cup. Older devices have a cast brass body which offers longer reliability. Newer models feature a plastic body and are cheaper than cast brass.
The diaphragm is connected to a rod that opens and closes to control water flow.
As the water in the tank rises, the diaphragm lifts the rod and acts as a pivoting lever to open the water supply valve. When the water reaches the top of the diaphragm, it pushes down on the rod and closes the water supply valve.
Diaphragm-type ballcocks are the least common type of valve, but they offer some distinct advantages over other types of valves. They are very resistant to clogging from mineral deposits and are the best seal against water leakage.
However, they can be more difficult to install and may require special tools for proper maintenance. Diaphragm-type fill valves with a cast brass body are the most expensive type of valve.
3. Piston-Type Ballcock or Float-Ball Fill Valve
The ballcock fill valve is one of the earliest toilet flush valve types. Made of a cast brass body and featuring piston-style fill valves, this type of fill valve uses a floating ball attached to a metal rod to control the flow of water into the tank.
The device has inlet and outlet valves. The inlet valve is opened by the water pressure, allowing water to enter the ballcock.
The float opens the outlet valve and allows water to exit the ballcock. When the float is lowered, the outlet valve is closed, and the inlet valve is opened. This allows water to enter the ballcock and raise the float.
When the float reaches a certain height, the outlet valve opens, and the inlet closes. This allows water to flow into the toilet tank and stop when the floating ball reaches its highest point.
Ballcock valves are available in different sizes and types. The most common types of ballcock toilet fill valves are:
- Adjustable: Adjusting screw controls the water level in the tank.
- Non-adjustable: Non-adjustable float balls have a fixed position for the float arm.
- Brass cup: Brass cup float balls have a cup that sits on top of the float, preventing it from increasing too high.
These valves are most often seen in older systems, but there might be other reasons for selecting this type of fill valve, such as needing an adjustable toilet fill valve. Some ballcock devices are not listed as anti-siphon. Wolverine Brass manufactures an anti-siphon ballcock as well as an adjustable-height anti-siphon plunger ballcock.
4. Floatless Fill Valve
Floatless valves have a more recent anti-siphon design. They have a plastic body and operate underwater using a diaphragm pressure-sensing mechanism.
The anti-siphon feature is integrated into the valve’s design in floatless systems, which operate based on water pressure. The anti-siphon feature in a floatless fill valve includes an air gap. T
his gap within the valve remains filled with air, preventing a direct connection between the tank water and the supply line. Should any reverse flow occur, the air gap stops the backflow of tank water.
5. Pressure-Assisted Fill Valve
Mainly found in commercial or institutional buildings, pressure-assisted valves are used specifically in pressure-assisted toilets. They manage water and air pressure refilling the sealed tank after each flush. These systems are known for their efficient water use, but they are noisier than traditional systems.
When to Replace Your Toilet Fill Valve
Over time, toilet fill valves begin to wear out. This normal wear and tear is due to the components’ constant movement and exposure to the water in the tank. As a result, it’s important to be familiar with the two common symptoms of a failing valve:
- The toilet takes a long time to fill. One common symptom is when it takes longer to fill up after being flushed. This extended fill time is because the valve can no longer open fully, reducing the water flow into the tank. If you notice this symptom, it’s probably a good time to replace your valve.
- The system is leaking. This is usually caused by worn-out seals, which can no longer prevent the water in the tank from escaping. Any leaking will cause it to fill with water more frequently. If you hear the tank filling at regular intervals, even when it’s not in use, that’s a tell-tale sign that you need to check your valve and possibly replace it.
Fortunately, replacing your valve is one of the least expensive plumbing projects you can be faced with.
Common types of toilet fill valves include:
- Float-cup valve
- Diaphragm valve
- Ballcock valve
- Floatless valve
All types of valves should meet current plumbing codes and be designed with anti-siphon protection to prevent water from overflowing from the tank into the bowl. However, each type of fill valve has its own advantages and disadvantages.
Frequently Asked Questions
Are There Different Types of Fill Valves for Toilets?
Yes, there are different types of fill valves. They are designed to accommodate different plumbing setups.
The most common types are Float-Cup (widely used in modern systems), Ballcock or Float-Ball (standard in older models), Pressure-Assisted (intended for pressure-assisted models), Diaphragm Fill Valves (found in older designs), and Floatless Fill Valves (used in low-pressure systems with a pressure-sensing mechanism instead of a traditional float).
What Are the Two Types of Flush Valves?
Flush valves come in two main types, based on their flushing mechanisms and design. Flapper-style flush valves are the most common type found in residential homes.
The flapper style features a rubber or plastic flapper that covers the opening at the bottom of the toilet tank. Canister (or tower) style flush valves are often found in newer or more advanced models. Instead of a flapper, these valves use a cylindrical canister that lifts vertically to release water for flushing.
What Kind of Valve Does a Toilet Use?
There are two main types of valves – the flush valve and the fill valve. They work in tandem to ensure the system operates efficiently, filling and emptying water as needed for each flush.
When flushed, the device releases water from the tank into the bowl. The fill valve controls the refilling of the toilet tank with water after a flush.
From the traditional float-ball valves to the more compact and efficient modern systems, the choice of valve can significantly impact a toilet’s performance and water efficiency. Understanding the different types of fill valves is important as they play a role in the functionality and sustainability of the entire plumbing system.