The answer to 'why is my thermostat not turning on' is that there are several common causes, including a dead battery, wiring issues, or a problem with the HVAC system itself. The thermostat may not be getting power, the settings may be incorrect, or there could be a problem with the heating or cooling equipment.
Some common symptoms include the thermostat display being blank or unresponsive, the HVAC system not turning on when the thermostat is adjusted, or the thermostat not registering temperature changes. Solutions can range from simply replacing the batteries to more complex wiring or system repairs.