A master HVAC license serves as the highest level of a technician in the HVAC business in some states. Someone with a master HVAC license can be the contractor himself. If you have a master HVAC license, you are generally considered to be better than a journeyman (in terms of wage, experience, and expertise).nnMaster HVAC technicians repair and maintain HVAC equipment, manage the installation and repair, and ensure that the work follows the state building codes. Although the state-wise requirements vary, you need at least one year of work experience as a journeyman to be eligible for the state’s master’s examination in most cases.