1. In VAV systems with a return air fan, the fan provides _____.

2. The maximum safe concentration of carbon dioxide (CO2) in an occupied space is _____.

3. Assume a single-zone constant-volume system with an economizer is installed. In the occupied mode, when the thermostat calls for cooling, which of the following occurs?

4. A multi-zone constant volume system is well-suited for buildings in which _____.

5. What is one characteristic that sets VVT systems apart from the other approaches?

6. Which type of system is designed to maintain a constant supply air temperature between 50°F and 60°F year-round?

7. In a VAV system, the demand for heat is satisfied by _____.

8. When a parallel fan-powered VAV box is in the heating mode, the primary air damper is _____.

9. What characteristic makes a grille into a register?

10. The primary source of heat for a year-round packaged air conditioner is _____.

11. In order to modulate the flow of supply air, VAV systems may use inlet guide vanes on the fan inlet or _____.

12. Which type of economizer is capable of choosing between the use of outside air or return air, based on the enthalpy of the two airstreams?

13. The simplest form of economizer control is the _____.

14. The packaged unit accessory used to prevent compressor oil from absorbing refrigerant is a(n) _____.

15. Comfort is normally associated with the air properties of _____.