I think the wiring is messed up this gas furnace. Right now when the selector arm is in the "off" position the furnace is off. When you move it to the "on" position the furnace fire up and runs no matter the settings on the thermostat. The set and pilot setting are not important because the pilot is getting gas from before the valve. I would like to be able to leave the selector arm in the "on" position and have the thermostat turn the furnace on and off (like it is supposed to). The photo isn't the best but it should be good enough to diagnose the problem. Red wire is on #1 terminal, Black wire is on #2 terminal and #3 goes to the thermostat only.