Internal equipment heat gain and load density data have been updated in the newest edition of the ASHRAE Handbook. The organization revised the data because outdated internal equipment heat gain data can result in oversized systems and higher operating costs.
The 2013 ASHRAE Handbook–Fundamentals cover basic principles and data used in the HVAC&R industry, including information on building materials, load calculations, energy resources and analysis, refrigerants, indoor environmental quality, sustainability, controls and duct and piping system design. Major revisions were made to Chapter 18, Nonresidential Cooling and Heating Load Calculations, including the new internal heat gain data and recommendations, an elevation correction example and an equation summary.
Older assumptions were based on out-of-date computer, copier and printer heat gains. The new data in the Handbook chapter reflect ongoing ASHRAE Research results. The chapter also includes an entirely new master example section based on the renovated ASHRAE Headquarters building. The updated example reflects current practice in energy efficient building construction, lighting loads and updated Standard 90.1, Energy Standard for Buildings Except Low-Rise Residential Buildings, compliance, as opposed to the previous example, which reflected 1990s practice.
Chapters in the ASHRAE Handbook are updated through the experience of members of ASHRAE technical committees and through results of ASHRAE Research reported at ASHRAE conferences and published in ASHRAE special publications and in ASHRAE Transactions.