Old thermostat Honneywell T87F has 6 wires, no heat pump

New thermostat Honnewelll RTH 7400 no heat pump - Where does the ORANGE or O wire go if notheat pump?:confused:

Usually the cable for a furnace-A/C doesn't even have an orange wire. Best thing is to go to the furnace and note the terminal markings and wire colors. Perhaps even rearrange the wires to follow the common convention as given in the sticky at the top of this forum. i.e.. a red wire running from R to RH and RC, a white one from W to W, etc.

If your cable doesn't have red, white, yellow, and green, use the colors you do have, just get the same wire on the same terminal at both ends.