Why is my AC thermostat blank?
Why is my AC thermostat blank? If your thermostat wall does not have a c-wire, or common wire, your thermostat most likely is not hooked up to your HVAC system for its power and needs batteries. When your screen is blank, it could indicate you need to replace the batteries. Most thermostats display a low-battery symbol when the juice is running low. Why is my venstar thermostat blank? The screen is blank Very low likelihood possibility that popping the thermostat off of the subbase for a few seconds then putting it back on might restore proper operation. Check the circuit...