Many Standards can be used for building HVAC, but the most elaborate standard is the ASHRAE (American Society for Heating Refrigerating and Air conditioning Engineers). The ASHRAE Handbooks cover all the aspects of the HVAC design. You can check in particular the ASHRAE Standard 90.1-2004, it's the energy standard for buildings except low-rise residential buildings.
You can also check in parallel the SMACNA (Sheet Metal and Air conditioning Contractors' National Association) Manual. It regulates the installation of HVAC systems and equipments...
The British Standards are also good but I would go for ASHRAE and SMACNA.