This is a reaffirmation of ANSI/ASHRAE Standard 78- 1985, which was reaffirmed in 1997 and 2003. This standard was prepared under the auspices of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). It may be used, in whole or in part, by an association or government agency with due credit to ASHRAE. Adherence is strictly on a voluntary basis and merely in the interests of obtaining uniform standards throughout the industry.

This standard is intended to provide a method for measuring the flow capacity of refrigerant suction line filters and filter- driers. The changes made for the 2007 reaffirmation were updates to the Bibliography.

This standard establishes a method for measuring the flow capacity of refrigerant suction line filters and filter-driers.

This test method is intended for use on both sealed and replaceable element type suction line filters and filter-driers of all types.

The test method is based on using air as the testing medium and calculating the results to refrigerant gas flow under various application conditions.