What Is a Foot Valve and How Does It Work?

A foot valve usually installed at the bottom of the water pump or pipeline. The foot valve consists of a valve body, a check mechanism (like baffle or valve core), and a filter screen.

How does the foot valve work?

The primary characteristic of a foot valve is to prevent water from flowing returned the pipe. When the pump starts, suction opens the foot valve, allowing water to enter the suction pipe; after the pump stops, the valve closes and water column pressure to prevent backflow and avoid re-priming. The screen blocks particles and protects the pump.

Types of he foot valve

1.Membrane foot valve

Internally, it contains a cylindrical rubber diaphragm encased in a steel mesh. When suction is generated within the mesh, the diaphragm is pushed, allowing fluid to pass through the valve.

2.Ball foot valve

This type of valve uses a cylindrical, inclined valve chamber and seat to guide the movement of a ball. As fluid flows in, the ball moves with the valve chamber; as the flow rate decreases, the ball slides down the valve chamber onto the seat. This type of valve is primarily used for treating contaminated water.

Types of he foot valve

1.Advantages

Built-in filter: Blocks particles from entering the water system, protecting the pump.

Corrosion resistant: Commonly made of materials such as stainless steel, PVC and brass, appropriate for corrosive environments.

2.Disadvantages

Prone to clogging: The filter screen is easily clogged by deposits, requiring regular cleaning.

Difficult installation and maintenance: Foot valves are set up at the discharge of a pump system and this makes it difficult to access them.

The Importance of the Foot Valve in Pump Systems

Foot valves are an important component of pump systems, their primary function being to prevent backflow. Foot valves are simple in structure and easy to use, and are widely used in systems such as water wells, irrigation, industrial fluids, fire protection, and HVAC.