Where is the moisture indicating sight glass typically located?

The moisture indicating sight glass is typically located in the filter drier. This component is crucial in refrigeration and air conditioning systems because it serves to remove moisture from the refrigerant. The sight glass allows technicians to visually inspect the refrigerant, checking for moisture and other contaminants. When moisture enters a refrigeration system, it can lead to ice formation, corrosion, and other serious issues that impair system function.

The filter drier is specifically designed to trap particulate matter and absorb moisture, making it an ideal location for monitoring vapor quality. A technician can look through the sight glass and determine if the refrigerant is clean and dry, which is essential for efficient system operation. If the sight indicates the presence of moisture, it signals that the filter drier may need to be replaced or that there is a problem elsewhere in the system.

In the context of the other components listed, while the expansion valve, compressor, and condenser are integral to the refrigeration cycle, they do not serve the same function as the filter drier in terms of moisture removal and visual moisture indication.