An HVAC technician can install, repair, and provide maintenance on heating and air conditioning systems. Exterior wall vent leading to an HVAC system. HVAC technicians install, repair and maintain heating, cooling and venting systems.HVAC technicians are expected to be skilled in air conditioner repair.hen an HVAC technician is associated with the installation of a new system, he or she will be proficient in reading blueprints connected to the installation, and will participate in the preparation of the space for the installation of the required equipment.