A tool for the analysis of heating, ventilation and air conditioning (HVAC) systems, methods for performing various analyses of an HVAC system with the tool, and a computer executable program used by the tool to perform the analyses are disclosed. The tool includes a processing machine, a database, a memory device having a software program executable by the processing machine, and a display device. The database stores information on each of a plurality of HVAC components and the software program is configured to identify and access information pertaining to at least one HVAC unit in an HVAC system from the database and is configured to generate a wiring diagram using the accessed information from the database that is displayed to the display device.