My gas furnace started blinking 4 flashes "High limit device open". So after playing around with that I switched out the high limit switch. My furnace still gives me the same message. However, it will fire up the gas burners without starting the blower. The burners will stay on without the blower until it overheats and I get the same message again, 4 flashes "High limit device open."

The blower will intermittently work though after the burners go out, so I know the blower does work. Is this a capacitor problem or a problem with the board? Or am I even close to the problem. I am not opposed to calling a tech out however I am an avid DIY'er and cannot stand it when I can't figure something out.

Any recommendations would be greatly appreciated.

Thank you.

To get heat temporary on you might switch your thermostat blower switch to on. Then recycle the 110 volt power to the unit and try again. It is possible that the blower control on the heat side is defective. I do not have a diagram for your furnace but that control could be on the main circuit board.