I just purchased a Honeywell vision pro 8000 stat. One of the options is an outside temperature sensor that displays the temp on each stat in the house (C7089U1006). Presently I have a 6 conductor thermostat wire running to each of my stats, only 4 conductors are used. Can I use those 2 extra conductors to wire in the outside temperature sensor or will this cause eratic readings due to interference. Do I need to run a seperate 2 conductor wire?