Humidifier control in the basement

the control for my central humidifier attached to the furnace is in the basement, where i guess, the humidity is higher than what it is in the rest of the home.
So the humidifier never turns on even when the furnace is running. Am i correct ??

 

It should be located inside the return duct where the air is as humid as what is pulled from the house. They do get dirty and don't last forever. If it's quiet listen real close as you turn the adjustment knob and you should hear a faint clicking sould at the point it would call for the unit to supply humidity. I had a similar problem and mine had to be truned to the max, over 50% to turn on. I removed it, cleaned it and adjusted the set screw to allow it to come on around 20%. To be honest I have no accurate idea what the humidity level is in the house but no one is getting static electricity shocks and the windows are not fogged up so I am figuring it's about right.