The paper presents newly developed dynamic simulation models of chillers for energy consumption evaluation of HVAC (heating, ventilating and air-conditioning) systems. The dynamic chiller simulation models are developed for absorption chillers and turbo chillers. The software makes energy consumption prediction not only for steady state operation, but also for start up and shut down operations possible. The tool also enables to test dynamic control stability of the HVAC systems precisely. Then it can be convenient to analyze the HVAC system and to improve the control performance. By the simulation tools with HVAC simulation tools such as HASP or HVACSIM+, we do believe the building commissioning will be become much more accurate.