Report "We just bought a house with an existing Aprilaire 600 humidifier. It is now heating season and we ae running the furnace. I turned on the humidifier and no water is getting to the pad.The water line is ok leading to the solenoid and the inline strainer is clear, but no water gets through the solenoid outlet side so it appears it is not opening. I cannot hear any clicking sound when I turn the manual humidifier dial on and off. Do I need to replace the solenoid? Or is there another problem?"