Upgrading EWC-ST-2E to NCM300

[pbstudios]

I am upgrading my old EWC-ST-2E to the NCM300 so that I can use NEST thermostats. The wiring on the old panel has me a bit perplexed when I compare to the NCM300 board. Specifically, the red wire going into the transformer terminal is jumpered from "R" in the system terminal and there is both a white and blue wire in the same terminal in the transformer. The blue wire is actually split off from the rest of the wire bundle that is connected to the system terminal.

How do I translate this to the new NCM300 board?

[Paul Z.]

Give me a call and I will go over the board with you, 1-800-446-3110X490.