thermostat blank

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    Thermostat Digital Screen is Blank - Is it the AC Unit or the Furnace? How do I troubleshoot?

    80UHG Series The thermostat runs both the AC unit and the furnace. There is no reading on the digital screen. I used a voltmeter to determine that it is out because no voltage is going to the thermostat. I've researched a bit and found out it may be due to a blown fuse in one of the units. How...