Ok, I have an outdoor wood furnace that I have hooked up to my central air unit. It is a water system with a condenser in the ducked work. I have all of that hooked up and all is working well with that. This is a propane Rudd achiever central heating/air unit. I want this to be a two thermostat system, propane as backup. I now need to hook up my other thermostat so that my fan only comes on when when I need heat. Can someone please tell me how to do this? Also the wire that is on there now looks like phone wire is that ok to use that kind of wire for the thermostats (5 wires blue not hooked up). Thanks to anyone that answers this post I really appreciate it!!!!