In the listed sequence of components on the liquid line from condenser to TEV, which component appears last?

• A. King valve
• B. Filter dryer
• C. Solenoid valve
• D. Sight glass

Answer: (D)

On the liquid line from condenser to expansion device, you want to pass high-pressure liquid through elements that isolate, dry, and allow a final check before expansion. The king valve sets up a convenient isolation point for service, so it tends to come early in the line. The filter dryer removes moisture and contaminants so what reaches the expansion valve is clean and dry. The sight glass is placed just ahead of the expansion device so you can visually inspect the liquid entering the TEV—looking for clear liquid flow and watching for any moisture or vapor pockets. That last visual check before the TEV is why the sight glass appears last in the sequence. The solenoid valve, when used on the liquid line, controls flow for specific operations but is not typically the final component before the expansion valve.