2020 ASHRAE Handbook adds DOAS and heat recovery

The latest edition of the ASHRAE HVAC system and equipment handbook has brought in sections about dedicated outdoor air system (DOAS) and heat recovery, among its list of many updates and revisions.

2020 ASHRAE Handbook – HVAC Systems and Equipment includes updated information to help system designers and operators select and use equipment that is the best fit for a particular application or scenario.

The book discusses various systems and the equipment (components or assemblies) they comprise, and describes features and differences. Subject matter experts on ASHRAE technical committees in each subject area have reviewed all chapters and revised them as needed for current technology and practice.

A new feature of the handbook is the annotatable PDF download. Users can highlight relevant text and add their own notes and comments.

The chapter on DOAS is entirely new and presents detailed information on this equipment, while the section about applied heat pump and heat recovery systems has new content on waste heat recovery, district applications and industrial process heat pumps.

Other updates that likely will impact many users include extensive revisions on system leakage and air dispersion systems; new content on psychrometrics, outdoor air, controls and industrial dehumidifiers; and new data on worldwide solar technology use.

Other revisions and additions include:

  • Chapter 18, Variable Refrigerant Flow, has new sections on modeling and system commissioning, and an updated system design example.
  • Chapter 20, Room Air Distribution Equipment, has updates for current technology, with new information on specialized components and air curtains.
  • Chapter 26, Air-to-Air Energy Recovery Equipment, has new information on heat pipes and desiccant and heat wheel systems.
  • Chapter 28, Unit Ventilators, Unit Heaters, and Makeup Air Units, has revisions on standards, controls, and fan selection for makeup air units.
  • Chapter 29, Air Cleaners for Particulate Contaminants, has updates on standards and performance testing.
  • Chapter 31, Automatic Fuel-Burning Systems, has added content on pneumatically and electronically linked gas/air ratio burner systems.
  • Chapter 38, Compressors, has revisions on general theory; screw and scroll compressors; and bearings, including oil-free technologies.
  • Chapter 44, Centrifugal Pumps, has new content on vertical, inline, split-coupled pumps; hydronic system pump selection; and differential pressure control.
  • Chapter 46, Valves, has new content on control valve sizing; electronic actuators; and ball, butterfly, flow-limiting, and pressure-independent control valves.
  • Chapter 49, Room Air Conditioners and Packaged Terminal Air Conditioners, has updates for efficiency standards.

ASHRAE has completed distribution of complimentary copies to members and is now offering this resource to non-members as well. It is available as a bound print volume, as a downloadable PDF, and online. Two editions are offered, one using inch-pound (I-P) units of measurement, the other using the International System of Units (SI). Individual chapters may also be purchased as digital downloads in PDF format.

Visit ashrae.org/bookstore or contact ASHRAE by phone at 1-800-527-4723 for more information.