Can the cooling wire (Y) be used to activate the furnace fan with a programmable thermostat?
When the t-stat is set to cool the fan comes on automatically when the temperature is set below the house current temp. But the fan will not turn off unless the house temp falls below the set temp. The (y) terminal does not need any wire attached to it. But do not try to make any terminal connections for anything but what it is intended for. You can easily burn the transformer, fuses or the low voltage wiring!!!