Furnace and A/C are working!!!

Honeywell R8239 "Fan Center"

I think the guy who installed this in the furnace was colorblind.

Signal comes in the bottom and goes out the top to the fan center in the cable on the left.

From left-to-right, white-stayed-white, red-became-yellow, green-stayed-green, yellow-became-blue, red-stayed-red and blue-became-red.  What a nightmare.  It looks like none of the wiring diagrams on the documentation for the fan center.

But rather than straighten out the world, I just mindlessly wired the new unit exactly like the old one.

Except I did not like the short wires between the bus shown in the bottom photo to the fan center.  while it looks tidy it means that fat, old, nearsighted men have to squat on the ground and do all the wiring inside the device.  It is SO much nicer when you can detach the device and hold it in your lap as you switch it over, one wire at a time.

This looks a lot more cluttered but every jumper is now 24" long.  I did not have blue or yellow wire so I wrapped the ends of white wire with the appropriately colored electrical tape.  I coiled up the extra and used twist ties to hold them.  I will use a cable tie to tidy it up even further, but for now I am basking in the glow of success.

Fan works.  A/C works.  Heating function bypasses the fan center and the fan powers up based on a temperature switch in the heat exchanger.  I think we are good-to-go!