HVAC Journeyman Practice Exam

According to the code, unless otherwise listed, air flow must first pass through which component?

1. The cooling coil

2. A diverter unit

3. A bypass duct

4. The heat exchanger

The correct answer is: The heat exchanger

The correct choice indicates that air flow must first pass through the heat exchanger unless specified otherwise in the code. This is crucial because the heat exchanger plays a vital role in transferring thermal energy between the air and the fluid (either a refrigerant or water) used in the HVAC system. This transfer ensures efficient heating or cooling of the air that is then distributed throughout the area being conditioned. By routing air through the heat exchanger first, it maximizes energy efficiency and maintains proper temperature control. Furthermore, it helps in preventing the potential for condensation that could occur in downstream components if warmer, moist air were to bypass the heat exchanger. In general, understanding the function of each component in an HVAC system is vital for ensuring that the system operates effectively and complies with industry standards and codes. Other components listed, such as the cooling coil or diverter unit, play important roles in the overall system performance, but they are secondary to the initial conditioning of air that the heat exchanger provides.