AT-84-13-2 -- ASHRAE 109—A Test Standard for Two-Phase Solar Collectors PDF

ASHRAE Standard 109, "Methods of Testing to Determine the Thermal Performance of Flat Plate Solar Collectors Containing a Boiling Fluid," provides standard test procedures for the growing number of two-phase flat plate solar collectors. The standard is modeled on ASHRAE Standard 93, "Methods of Testing to Determine the Performance of Solar Collectors."

The operating characteristics of boiling liquid collectors are described and compared to those of single-phase collectors. The important features of Standard 109 are presented, particularly those differing from their counter­parts in ASHRAE Standard 93. A list of results to be expected when testing under Standard 109 is presented and discussed. Some of the intentions and underlying considerations of the authoring committee are discussed. Potential uses of the standard are presented with an outline of additional work needed to maximize the standard’s usefulness to the solar industry.