The sight glass is the device that can visually determine the moisture content of refrigerants by showing bubbles when moisture is present. Other options like the filter-drier, accumulator, and crankcase heater do not provide visual indicators of moisture. Therefore, for assessing refrigerant moisture, the sight glass is essential. ;
The sight glass is the device that visually determines the moisture content of refrigerants, displaying bubbles when moisture is present. Other options, like filter-driers, accumulators, and crankcase heaters, do not provide visual indicators of moisture. Thus, the correct answer is the sight glass.
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