Help please, my boss tried to change the thermastat at work and he messed up. I don't know which wires are to go to which colours. I have 8 wires, 7 were originally used. The wire colours are red, white, blue, brown, black, green,orange and yellow. The orange was not used before. The t'stat has on top c, w, w2 and the bottom has r, g, y and y2. Can anyone help me?

Thanks

Is this a heat pump? If not, connecting the red to R, the white to W, and the blue to C should get you heat.

If it is heat pump, carefully study the directions for the thermostat.