HVAC Systems and Equipment

This chapter on HVAC systems and equipment has seven sections with several sub-sections in each section. After a brief introduction in Sect. 8.1, basic HVAC systems are covered in Sect. 8.2, including direct expansion (DX) cooling systems, chilled-water cooling systems, and steam-based heating systems. Section 8.3 covers chilled-water systems in detail including water-cooled, air-cooled, and evaporative condensers. Section 8.3 also includes coverage of different types of compressors, such as scroll, screw, and centrifugal compressors used in chilled-water systems. Energy recovery systems including heat recovery ventilators (HRV), and energy recovery ventilators (ERV) are covered in Sect. 8.4. Different energy recovery devices such as plate and frame heat exchangers, run-around coils, sensible wheels, heat recovery wheels, energy recovery wheels, enthalpy wheels, and their analysis for both summer and winter operations are explained in detail in Sect. 8.4, with the use of several illustrative examples and practice problems. Acoustics and noise control are covered in Sect. 8.5, including sources of noise and noise mitigation strategies. Section 8.6 covers vibration and vibration control in HVAC equipment and systems, including vibration isolation mechanisms such as elastomer pads, floor springs, and spring hangers. Constant air volume (CAV) and variable air volume (VAV) systems are covered in Sect. 8.7, with both single-zone and multiple-zone applications. Illustrative examples to compare CAV and VAV systems are presented in Sect. 8.7.