A C Wire Diagram. From there 3 wire cables black white and red are used between the switches with a final 2 wire cable going from the last switch to the light fixture. I am installing a honeywell rthwf with a taco sr the c terminal connection wire that the honeywell instructions are talking about provides power for the thermostats electronic control while the r and w terminal connections simply connect to the loop in your furnaces circulation pumps.
Although ive seen it stated in several places its not entirely correct to say that the c wire is what powers the thermostat. The presentation of the interconnections. Common i 2 c bus speeds are the 100 kbits standard.
Route and connect it to the horn power terminal.
Select the dark green horn feed wire 29. Select the orange electric fan feed wire 300. Keep in mind that the traveler terminals for red black wires are universal and will work regardless of which one the traveler wire is connected to. There will usually be about seven strands of fine wire.