Last Updated on July 16, 2023
A float valve and a float switch are two types of devices used to maintain the water level in a tank or storage container. Even though both devices are used for the same thing, what are the differences between float valves and float switches?
Float valves are devices connected to a float, which rises and falls with the level of liquid as the liquid level drops and regulates fluid levels in storage tanks. In contrast, float switches activate or deactivate pumps when liquid levels reach a specific level in a tank.
Both products control liquid levels in tanks but have some key differences. Please read more about the differences between the two devices and determine which is best for you.
What are the Differences Between Float Valve and Float Switch?
In the most general terms, a float ball valve controls the liquid level in a tank, while a float switch detects the fluid level in a storage container to start a pump. While both float valves and float switches are used to control the level of liquid in a tank, there are a few key differences between these two devices:
01. How They Work
The main difference between the two devices is how they are used. Float valves are typically used to control liquid flow in a tank or container by using a valve controlled by a float at the end of a lever.
For example, a float ball valve can fill a tank with water until it reaches a certain level. Once the liquid reaches the predetermined level, the float activates the valve and stops the liquid flow.
On the other hand, float switches are commonly used to control other devices, such as alarms and pumps. For example, if a tank starts to overflow, a float switch sensor can be used to activate an alarm or shut off the pump.
Similarly, if a tank starts to run low on liquid, a float switch can be used to turn on a pump to refill the tank. After all, these devices use floats to control the level of liquids.
02. Usage of Them
Float valves simply allow the float to be attached or removed without shutting off the water supply, whereas float switches might be manually turned off sometimes. Also, float valves are typically used for larger tanks and reservoirs, while float switches are often used for smaller tanks and sump pits
Household fixtures such as kitchen sinks and toilets typically have float valves to regulate water flow. Conversely, float switches are typically used in industrial applications such as fire-water towers and sump pits. An electrical circuit is triggered by the movement of a float to activate a pump or sound an alarm.
03. Constant Fluid Level
Both float valves and switches maintain the fluid level, but float valves maintain a constant fluid level as they draw fluid from another source. By contrast, float switches operate the pump or alarm system.
Float switches are installed inside the tank and use a float and a sensor to detect changes in the liquid level. When the float rises or falls to a certain point, the sensor activates the switch, which can turn a pump on or off.
04. Different Materials
When choosing the suitable float ball valve or float switch for a particular application, the material is one of the most important considerations. After all, different materials are better suited for different liquids and environments.
For example, stainless steel float valves are a good choice for clean water applications, while gunmetal float valves are better suited for dirty or corrosive environments. Meanwhile, cast iron float valves are often used in high-pressure applications.
Float switches and level sensors are manufactured from many different materials. Since stainless steel resists corrosion and can withstand a wide range of temperatures, it is a popular choice for switches’ outer parts.
Acetone and ammonia are both common industrial chemicals, and float switch sensors made from these materials are often used in hostile environments. Bronze and copper are often used in plating solutions, providing a corrosion-resistant finish.
05. Budget-Friendly
Both types of devices regulate liquid levels in tanks, but float valves are generally more budget-friendly than float switches. Because float switches are more complex, they typically cost more than float valves.
Float valves are typically very easy to use. All you have to do is attach the device to the tank and let it do its job. Float switches can be complicated to install and repair. You may need to hire an electrician to wire the float switch to your electrical system.
What are the Different Types of Float Valves & Float Switch?
Although the float valve and float switch work similarly, several types of each differ in how they are used.
Float Valves
A float valve is a mechanical device that regulates the flow of liquids and gasses by using a float to control the opening and closing of a valve. The float is usually connected to a lever that opens or closes the ball valve as the float rises or falls.
But there are two main types of float valves used in the control of liquid flow:
01. Direct Float Control Valve: This type of floating ball valve raises in response to the increase in liquid level within the tank. In this configuration, the main valve is operated by the movement of the arm unit of the float valve.
02. Pilot Operated Float Control Valve: As liquid levels increase in the container, the float rises to close the pilot valve. There’s a lot of liquid on the upper section of the primary control valve. The upper chamber comprises a diaphragm that pressures the primary valve to close.
The float descends with the level, allowing liquid to flow through the pilot line of the float valve. Due to this, the main ball valve opens to allow liquid to fill the tank. There are several possible locations for the main valve, either near the float valve or at an appropriate distance from it.
Float Switches
A float switch is a level sensor for measuring liquid levels within a tank. The device consists of a float, which is connected to a switch via a length of cable or rod. As the float rises or falls with the level of the liquid, it activates or deactivates the switch. A float switch controls liquid flow in two main ways:
01. Stem-mounted float switches: These switches are mounted on the stem and restrict float moves up and down along the stem. They function on a floating-point basis.
There are many stem-mounted float switches, including simple single-point switches with a single float or complex multi-point switches with up to seven floats on the stem. It is also possible to find single-point float switches in horizontal and vertical orientations.
02. Cable-suspended float switches: These switches are as flexible as the cables connected. Float switches that are cable-suspended will drift as far as the line allows if they are not tethered.
Although cable-suspended float switches are mechanically very similar, they can exhibit a much wider range of electrical characteristics than stem-mounted float switches. Simple wire float switches have only one switch point, while complex ones have four switch points and an integrated hysteresis.
How Does a Float Switch Sensor Work?
A float switch is a sensor that detects the liquid level in a tank. The float sits on top of the liquid and floats up and down as the level of fluid changes. Magnets and reed switches are connected to the float.
The magnet moves when the float rises or falls and either opens or closes the reed switch. This action causes the float switch to either turn on or off, depending on the float’s position. Thus, the float switch can automatically control the liquid level in a tank.
As the float rises, it activates a switch that sends a signal to the control panel. The control panel can then use this information to turn pumps on or off or indicate the liquid level in the tank.
Float switches are widely used in industrial and commercial applications, such as oil and water tanks, but they can also be used in residential settings, such as sump pumps.
How Many Wires Can be in a Single Throw Float Switch?
Float switches are often used in sump pumps, sewage pumps, and automatic bilge systems. Most float switches are activated by a magnetic sensor, which floats on the surface of the liquid. When the liquid level reaches a certain level, the switch is activated and triggers the pump.
But, not all float switches are created equal. Some float switches only have room for two wires (such as a single-pole single-throw float switch), while others may have four or more wires.
It depends on the float switch’s design and the application’s needs. But in general, most float switches only require two wires: one to power the device and one to signal the pump to start.
How Many AMPs Can a Float Switch Handle?
Typically, a float switch can handle a maximum current of 0.5000 amps and a maximum DC voltage of 200 volts. But, it is always best to check the specifications of the particular float switch you are using.
While this is more than sufficient for most applications, there are some cases where a higher-rated switch may be necessary. When in doubt, it is always best to consult with an experienced engineer or electrician.
What are the Applications of a Float Switch and a Float Valve?
Float valves and switches are similar devices used to control water flow in a pipe. Though they may appear identical at first glance, float switches and valves serve two different purposes.
Float switches are commonly used in fire-water towers to monitor the water level and activate pumps in the event of a fire. They can also be used in sump pits to detect when the fluid level has risen too high, triggering an alarm or activating a pump to remove the water.
Float switches can monitor the liquid level and prevent overfilling in cisterns and other large storage tanks. Similarly, float switches can be used in fuel tanks to avoid overloading and leaks and in coolant, tanks to maintain proper coolant levels.
Float valves are commonly used in kitchen basins, reservoirs, open and closed storage tanks, condensate tanks, and swimming pools. They are also used in industrial wastewater treatment and oil refining.
In each of these applications, the floating ball valve helps to maintain a constant level of liquid by opening and to close the passageway as needed. In some cases, the float valve may also regulate airflow or other gasses.
What’s the Best Place to Buy Float Valves For Water Tanks?
Shopping online makes finding the perfect float valve for your water tank easier. With a vast selection of options, you can easily browse in minutes and purchase. No need to wait around for store hours or sift through limited inventory.
Additionally, conducting online research can help you find the best products and the most reliable sellers. To make your selection even easier, our article on best float valve for water tanks contains detailed information on top choices.
Our top float valve reviews and buying guide can help you make an informed purchase decision and feel confident investing in a product that suits your needs.
Float Valve or Float Switch, Which is the Best for Daily Use?
If you are looking for a reliable and affordable way to top off your water tank automatically, then a float valve is a great option. A floating ball valve is a simple device that uses the weight of the water to regulate the flow of water into the tank.
Float switches are another popular option for automatically topping off your water tank. Still, instead of a traditional valve, a float switch uses an electronic sensor to detect when the water level in the tank drops, which can be more reliable in some cases. Even though they cost more than float valves, they are more reliable and require less maintenance.
While both devices are great options for keeping your tank full, using a float valve for most daily life applications is recommended. Float valves are more affordable and easier to install and have a longer lifespan than float switches.
