Humidifier

My humidifier stopped adding moisture to the house. I didn't know why. It sounded like it was running, but when the house humidity fell below 20% I knew something was up. The water pad was the issue, that's what. Can you tell which one is new and which one is the fossil?

You see, a standard whole house humidifier works much like the ones that you sit on your bedroom dresser or the floor of your apartment, it's just connected directly into the output of the furnace. When the humidistat calls for moisture, a little valve opens releasing water onto this water pad (pictured above) which acts like a sponge. The water trickles down it vertically like a water fall. Then a fan kicks in and blows air through the pad evaporating the water into the outbound air flow of your duct work. It's just that simple. If the water pad has scale buildup (from the contents left behind when water evaporates [like calcium, iron, etc]) then it stops holding onto water and you have no water to evaporate. These need to be replaced a couple times a year.

UPDATE: After replacing this part, I still think I have some issues. It might be the solenoid (the valve that opens to allow water to flow). That's a pricier item. I have more work to do.