Aprilaire whole house humidifier not working/ wired right

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dborns

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We just moved to a new home, so I'm starting to work on some of the issues that we've encountered. I noticed that it was getting a little dry in the house, and our Nest thermostat is showing 26% humidity, so I started looking at the humidifier. First off, I saw two wires on the solenoid, and two wires, (red/ white), coming from inside the heater. One of the wires on the solenoid was not connected to anything, and the white wire was also disconnected. I tested the red and white, and got 24volts, so I hooked the red and white to the two wires on the solenoid. I heard the "click", so I knew the solenoid was good.
Right where all the wires are, I found two more red and white wires, and they weren't connected to anything either. I traced these wires, and they go up into the humidifier control. So the control box, has no way of increasing or decreasing the amount of water to flow, as its not hooked up to anything.
I fired up the furnace, and I do have a little bit of water dripping into the filter box, but even if I let it run for 20 minutes, there's still no water going through the drain tube, and the filter is barely damp.
So my question is, I have the red and white power wires going to the two wires on the solenoid, but what do I connect the red and white control box wires too?
 
Here are the red and white power wires coming from the furnace and connected to the solenoid

IMG_7311.JPG
 
And here are the red and white wires coming from the humidifier control box that aren't connected to anything.

IMG_7312.JPG
 
Any suggestions? I've googled how to wire a humidistat, but I've not found any schematics on wiring it with the solenoid. I could really use some help because it's getting really dry in the house.

I'm thinking about it like wiring a light switch, but I don't want to fry something by doing it wrong. I have the red/ white power wires, the two yellow wires on the solenoid, and the red/ white coming off the humidistat.
I'm thinking if I run red from power to red on humidistat. Then white from power to one of the wires on the solenoid, then the white from the humidistat to the other yellow on the solenoid. The humidistat would then be the "light switch".
Does that sound correct?
 
Post a link to the install manual for your humidifier.

The 24vac from the transformer should go through the humidistat and then to the solenoid-controlled water valve.

On mine the 24v is halved when running the valve.
 

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