In the year 2014, Bangalore ISHRAE Chapter, undertook to make this Handbook more comprehensive, with a lot of additional data, in the I-P System. In this revision, information has been added to make this Handbook relevant, and in line with the latest trends, especially the efficiency standards for HVAC Equipment, VRF / VRV systems and green building norms . In this Databook, the weather Data is udated as per latest ISHRAE Indian weather Data Handbook.The I-P System is retained in this version also. An addition of the CLTD Method of Heat Load Calculation has been made, to make available more precise Heat Load Calculations, linked to Indian weather data. We hope to make Heat load Calculations less cumbersome and more precise, so that all ISHRAE members can use it.