NATE Air Conditioning and Heat Pumps Practice Exam

Which of the following statements about the installation of an electric air cleaner (EAC) is true?

1. An EAC should be wired to operate only when the ON/OFF switch is in the "ON" position and the supply air blower is operating

2. The control voltage supplied to an EAC can be as high as 5,000 V

3. The primary function of an EAC is odor removal

4. When the relative humidity is low, an EAC should be operated only in the heating mode

The correct answer is: An EAC should be wired to operate only when the ON/OFF switch is in the "ON" position and the supply air blower is operating

The statement indicating that an electric air cleaner (EAC) should be wired to operate only when the ON/OFF switch is in the "ON" position and the supply air blower is operating highlights an important aspect of EAC functionality and safety. When installed correctly, an EAC works in conjunction with the air handler or furnace blower. This ensures that the air being cleaned is consistently circulated, maximizing the efficiency of air purification. In this configuration, the EAC is engaged when the system is actively moving air, allowing for optimal performance and filtration of airborne particles. Operating the EAC only when the blower is running helps maintain the unit's lifespan and effectiveness by preventing it from running in static conditions, where it wouldn't contribute to cleaning the air. The other options, while potentially factual in different contexts, do not speak to the critical aspect of operational safety and efficiency that is central to the function of an EAC. The control voltage points to potential hazards and design considerations rather than operational requirements, the statement about odor removal does not encompass the primary function of an EAC—which is particulate removal—and the directive concerning relative humidity lacks relevant context for standard operation modes. Thus, the focus on the operational relationship between the EAC, ON/OFF switch, and