Here is a universal thermostat wiring colour scheme:

Cooling - Y - yellow or blue
Heating - W - white
Fan - G - green
24V - R - red

Always be sure to match to the terminations on your furnace. Some wire colours may vary so take note and duplicate on the t-stat.

[This message has been edited by CIWS (edited January 11, 2004).]

When I purchased the house, the previous owner had removed the hallway light. Want to put the light back up, there are 2 white, 2 black, ground coming out of the wall. Do I connect all the wires to the light?