Which of the following is NOT a method to reduce refrigerant loss?

Using open systems frequently is not a method to reduce refrigerant loss because open systems inherently allow for the escape of refrigerants into the atmosphere. Open systems do not maintain a closed loop, which is crucial for minimizing refrigerant loss. When refrigerants are exposed to the atmosphere, they can evaporate or leak, resulting in higher overall losses.

In contrast, employing proper recovery techniques, minimizing open-system exposure, and ensuring all connections are secure are all effective strategies for reducing refrigerant loss. Proper recovery techniques involve using tools and equipment designed to reclaim refrigerant safely and efficiently. Minimizing open-system exposure limits the amount of time that refrigerants are allowed to escape into the atmosphere. Ensuring secure connections helps prevent leaks that can occur at joints, fittings, and connections where refrigerant might escape. Therefore, the correct approach to minimize refrigerant loss focuses on maintaining closed systems rather than frequently using open systems.