I have 4 wires coming out of the wall for thermostat. Black and Red are twisted together and Yellow and Green are twisted together. The Hunter (Model 44100) thermostat has 4 terminals marked R,G,W,Y.There are no markings on the old 2 terminal thermostat. Do I connect the BlackRed wires to the R terminal and the GreenYellow wires to the W terminal? I have just Oil furnace and no A.C. Thank You