Question 27Refrigeration & AC - Assistant Engineer

The correct answer is C. The illustrated device labeled C would be the least accurate for weighing-in a refrigerant charge. This is because C appears to be a simple hanging scale, which is not a precise instrument for measuring the small quantities of refrigerant typically used in refrigeration and air conditioning systems. More accurate options would be a digital scale (A) or a precision balance (B or D), which can measure weight to a higher degree of accuracy and resolution. While a hanging scale may provide a rough estimate, it would not be suitable for the precise charge measurements required when servicing refrigeration equipment. The other options, being more precise measurement tools, would be more appropriate for this purpose.