When electrical signal is sent to an irrigation valve solenoid, which occurs?

When electrical signal is sent to an irrigation valve solenoid, which occurs?

• A. The water pressure above the diaphragm decreases.
• B. The flow of water is restricted by the diaphragm.
• C. The valve energizes to close.
• D. The solenoid pulls the plunger up, opening the valve.

Answer: (D)

When power is applied, the solenoid acts as an electromagnet and pulls the plunger upward. That movement releases the diaphragm’s seal against the valve seat, allowing the upstream water pressure to push the diaphragm and open the main passage. In irrigation valves, this is the typical action: energize to open, de-energize to close. So the correct description is that the solenoid pulls the plunger up, opening the valve.

When power is applied, the solenoid acts as an electromagnet and pulls the plunger upward. That movement releases the diaphragm’s seal against the valve seat, allowing the upstream water pressure to push the diaphragm and open the main passage. In irrigation valves, this is the typical action: energize to open, de-energize to close. So the correct description is that the solenoid pulls the plunger up, opening the valve.