How does a water solenoid valve work?

When the water solenoid valve is switched off, the water pipe is closed by a plunger or rod made from ferrous metals such as iron or steel. Within the body of the solenoid, the rod is wrapped in a copper coil. When the system is switched on, an electrical current passes through the coil, creating a magnetic field. The magnetic field moves the rod out of the pipe, opening the way for water to flow through.