Testing of solar collectors according to ASHRAE standard 93-77

Two test facilities have been built at NBS in accordance with ASHRAE Standard 93-77, one for modular water-cooled collectors and the other for air heaters. The purpose of this paper is to describe the recently adopted test procedure, to provide a description of the facility at NBS, and to give results of a complete series of tests made according to the Standard on several commercially available collectors.