Where should liquid stop valves be placed in the high side of a refrigeration system?

Liquid stop valves should be placed in front and after the bullseye sight glass to ensure proper functioning and monitoring of the refrigeration system. The sight glass is critical for observing the refrigerant status, allowing technicians to confirm whether liquid refrigerant is present and to monitor the system's operation.

Positioning the stop valves around the sight glass allows for easy isolation and replacement if maintenance is needed, without disrupting the entire system or losing refrigerant. This placement also enables technicians to perform necessary checks while maintaining system integrity. Therefore, having them before and after the bullseye sight glass provides a practical and functional advantage in managing the refrigeration system efficiently.