NATE Air Conditioning and Heat Pumps Practice Exam

Which of the following low-voltage wires is typically used to carry power to the thermostat subbase?

1. Green

2. Red

3. White

4. Yellow

The correct answer is: Red

The correct answer is the red wire, as it is typically designated for providing power to the thermostat subbase in HVAC systems. The red wire is generally linked to the power supply, often connected to the R terminal on the thermostat, which is responsible for delivering 24VAC from the transformer to the thermostat. This power is necessary for the thermostat to function, allowing it to control the heating and cooling system effectively. In HVAC wiring, each color serves a specific function. For instance, green wires are usually associated with the fan control, while white wires are often linked to the heating system, and yellow wires typically control the cooling system. Understanding these designations is crucial for proper installation and troubleshooting of heating and cooling systems.