upgrade from communicator tstat to wifi ..help
I have a carrier a/c unit and Lennox furnace w heat pump. It has a air handler that only has the tstat connected for communication. The wiring shows V+(red) and Vg(white) for inputs at handler and red and green at the original carrier tstat. I am trying to upgrade to a WiFi thermostat (iris) but need the full remaining w, y, b wires. I have tried to disconnect the tstat wires at handler side to "break" communications, thus keeping
the 5 wires connected at both ends. Still doesn't work.