HVAC-R refers to the refrigeration component of heating, ventilating, and air conditioning work. Revelant certifications for HVAC-R include EPA 608, a part of the Clean Air Act. These regulations require that technicians must be certified who work on equipment that could release refrigerants into the atmosphere. A person must earn EPA 608 certification to perform certain work on HVAC equipment such as air conditioners or refrigerators. You must get EPA 609 certification to work on car, truck, or tractor air conditioning equipment.