In this Issue

• New video on Ductsize Basics

• Elite Software YouTube Channel

This monthly newsletter will announce new software, tradeshow events, and tips on using existing software. See previous newsletters here.

Both ASHRAE and ACCA provide duct design procedures. ACCA calls their method Manual D, and it is primarily intended for sizing residential duct systems. You can read more about Manual D here. Elite Software has automated the Manual D procedures within Rhvac and a stand alone web application called Manual D Ductsize Online, as seen here.

ASHRAE offers a book for designing commercial HVAC duct systems called Duct Systems Design Guide, as described here. The primary difference between the ASHRAE and ACCA duct design procedures has to do with how fitting losses are calculated. ACCA uses an equivalent duct length approach for fittings, i.e. a 6" elbow might equal to 20 feet of straight ductwork. This is a simple approach for fitting losses that is reasonably accurate. ASHRAE, on the other hand, has created a table of fitting loss coefficients for all the common fittings found in commercial duct systems. These loss coefficient tables provide very accurate pressure loss calculations for fittings used in a wide variety of operating conditions.

Ductsize is a Windows computer program that implements the ASHRAE duct design procedures. There is a low cost $299 version that uses only the equal friction calculation method like ACCA Manual D, and there is the upgraded option, $200 more, that also provides the advanced "static regain" method of sizing ductwork. Besides sizing ductwork and calculating pressure losses, Ductsize also does a sound analysis as well.

A major bonus for Elite Software Chvac users is that Ductsize can import data from Chvac. All of the general project data from Chvac can be imported along with all the calculated room cfm (or liters/second) values as well.

Click here to see more details on Ductsize and download a trial version. Be sure to check our web site at www.elitesoft.com for even more info. Many programs have received free downloadable updates. Go here to see if there are updates relevant to your software.

If you have questions on any topic, please feel free to call 800-648-9523 or 979-690-9420, or send email to info@elitesoft.com.

Sincerely,

Bill Smith
President, Elite Software

National Comfort Institute recommends Elite Software for High Performance Contractors