Aprilaire Solenoid Valve 24 Volt For Humidifiers is designed to provide reliable control for your humidifier system. This solenoid valve operates at 24 volts and is compatible with Aprilaire humidifier models 400, 500, 600, and 700. It ensures efficient water flow management, helping maintain optimal humidity levels in your home for improved comfort and air quality. Easy to install and built to last, this valve is an essential part for maintaining the performance of your humidifier. Model Number: 4040