When I turn on the heat for my Nest Thermostat, the system blows lukewarm air. When I turn it off, the furnace kicks in and the heat comes on. The heat-on-but-thermostat-off pattern continues in cycles until I turn the Nest to cooling and then turn it off again. It doesn't seem to respond to temperature settings at all. If the house is at 65 and I set it for 68, it will just turn on the heat and keep going, blowing past 68 without stopping. What is happening? Do I need to install a power connector? I don't have a C wire to my thermostat and I'm wondering if this is a power issue.
