scratch that i took the thermostat off the wall and see no blue wire. now my problem is nothing comes on when you turn it to heat the relay just clicks and thats all the booster fan or nothing comes on at all????

WHAT IS THE BLUE WIRE THAT COMES OUT OF THE WALL FROM THE THERMOSTAT SUPPOST TO BE CONNECTED TO I FOUND IT BARE AND NOTHING COMES ON NOW AT ALL NO HEAT OR AIR

Nothing comes on at all. The flut booster is usually the first to come on but nothing does. The box that makes the clicking noise looks to be the one with the wires from the thermostat going to it

My evcon wont light or turn on any fan at all.The a/c works fine but when you turn it on heat the furnace just clicks and does nothing. The exhaust fan is only 2 years old and I replaced the ignitor last November. And I also don't see any lights blinking anywhere just does nothing but click once and...