@Neal, I checked the ones I could get to and tightened everything up, but nothing was really loose. Below is what I did with pictures.
So turn off the furnace breaker and remove the cover pull the screws on the outlet and just pull it out so you can see how it is wired and wire colors
Here is what I have.
1. Coming into the outlet from the on/off switch are 3 wires, white, black, and green.
a. The white wire runs to the upper left side screw,
b. The black wire runs to the upper right screw,
c. The green wire runs into a screw cap, which runs into the hole in the back of the outlet into the furnace (junction box?). Inside the box, it is grounded with a small screw.
2. There are 2 wires, a white one running from the lower left side screw to the box at the bottom of the outlet, and a black one which runs from the hole in the back of the outlet from the junction box into box at the bottom of the outlet.
3. Finally, there are 5 wires running into the hole in the back of the outlet (that runs into the box inside the furnace). They are...
a. the green wire explained above in 1c.
b. a white wire which runs from the lower left side screw to the control box plug in "LINE-N" aka "E7"
c. black #1 runs from the upper right side screw to the door switch
d. black #2 runs from the lower right side screw to the control box plug in "EAC-H" aka "E18"
e. black #3 runs from box under the outlet to the control box plug in "HUM-H" aka "E28"
So now what? LOL