SACRAMENTO, Calif. - TheSmall HVAC System Design Guide, produced by the California Energy Commission (CEC), offers design guidance on how to improve the installed performance of small packaged rooftop HVAC systems in commercial building applications. The document is written for architects, engineers, and design/build contractors.

The guide includes information and advice on overall building design practices to minimize HVAC loads, unit selection and sizing, distribution and control system design, commissioning, and operations and maintenance. According to the guide, by applying the integrated design principles in this document, the energy consumption and costs of buildings with small HVAC systems can be reduced by 25 percent to 35 percent.

Along with integrated design, other strategies suggested in this document focus on establishing and maintaining efficient operation of systems as they are installed in the field. Problems with equipment and controls (economizers, fan controls, thermostat programming), in-situ airflow and fan power, refrigerant charge, and operation/maintenance practices that can lead to poor system performance are addressed.

To download a copy of the guide in PDF format, go to

Publication date: 04/04/2005