Aprilaire 760 won't start

My humidifier wont start. I can hear a clickl when I rotate the humidistat from off position. But i never see the water flowing out of the solenoid valve. I changed the solenoid valve thinking it must be faulty, but still this wont work.

I am planning to check if the voltage (24V) is coming in to the solenoid valve. My other question is if i remove the front part (cover) of the humidifier from its base which has a power cord connected and plug it in, should the fan work?

What else should I do?

Sunny