I am about to install the ecobee 3 lite thermostat. On the thermostat end, there is no C wire - just the typical 4 wires - R,Y,W,... On the furnace end though, there is white C wire too, which I do not know where it leads to (definitely not coming to thermostat).
Given the situation, following are questions I am looking answers for: 1. Can I simply remove the existing C wire and replace with the C wire from the PEK kit from ecobee? Wondering what else may break in the house. 2. Can I simply keep the existing C wire as is, and add the C wire from the PEK kit in addition, at the same terminal?
Any info or any tips that can help me out in this situation are highly welcome.