If you read our article about check valves, then you already know the basic operation and purpose of a foot valve. A foot valve is actually a type of check valve used in pumps at the suction base, or foot, of the pipe. It allows liquid to flow in one end of the valve and out the other end when a pump is turned on. When the pump is turned off, it prevents fluid from flowing in either direction while at the same time, allowing the pump to stay primed, with liquid remaining in the pipes for the next time it’s needed. This protects the pump from damage that can occur with backflow.

Since foot valves are installed at the bottom of a well or tank, the weight of fluid on top of the valve is enough to close the valve, preventing the flow of fluid when the pump is off. A screen at the valve opening prevents debris from entering and clogging the valve.

There are also flapper-style foot valves that use a flapper to control the flow of liquid. When the pump is turned on and pressure increases on the inlet end of the valve, the flapper is forced open. When the pump is turned off, gravity and the pressure of the backflow of liquid closes the flapper.

Foot valves are essential, not only to protect pumps from backflow, but also to allow pipes to remain primed with liquid, saving energy and ensuring it’s ready when required.

What are common uses of foot valves?

Like check valves, foot valves are versatile devices used in many domestic and industrial applications. They are essential to ensuring one-way flow of liquids and preventing backflow that can damage pumps.
One of the most common uses of foot valves in homes is water wells or irrigation pump systems. Since the foot valve is installed at the bottom of the well, it allows the jet pump to always be primed and ready to use. Another domestic use of foot valves is in pond pumps for aeration or irrigation.

In industrial applications, pumps may be used to move water from a lower level to a higher level, especially in buildings with multiple stories. As you can imagine, it takes a lot of energy to move that water. So, when the pump is turned off, or the water isn’t needed, it saves energy to keep the pump primed so water is maintained in the pipes at all times and ready when it’s needed again. Foot valves installed at the base of the pump prevent the flow of water from the pump, and also hold the water that’s currently in the pipes.
Other applications that use foot valves include underground wells. Strataflo manufactures all-purpose foot valves for multiple applications, including cold water, ethylene and glycol, and fuel pump systems.

Foot valves are versatile devices that you’ll find in use around the world.