ARLINGTON, Va. - The Air Conditioning Contractors of America (ACCA) has announced that Manual S has been approved as a national industry standard by the American National Standards Institute (ANSI).

Manual S, "Residential Equipment Selection," is a guide for residential heating and cooling equipment selection. It is one of a series of ACCA manuals used in the design and installation of residential HVAC systems.

Manual S is the third ACCA manual to be recognized as an ANSI standard. Manual D, "Residential Duct Design," and Manual J, "Residential Load Calculation, 8th Edition," have already been approved as ANSI standards.