What could indicate a refrigerant leak during system inspection?

The presence of traces of oil during a system inspection is a strong indicator of a refrigerant leak. Refrigerants, such as those used in HVAC systems, can seep out of components where there are cracks, loose fittings, or seals that have deteriorated. When refrigerant escapes, it often carries some compressor oil with it, as the oil is used to lubricate the compressor and is mixed with the refrigerant. Finding oil traces around connections, joints, or on the ground beneath components suggests that refrigerant is escaping from the system, thereby indicating a leak.

While low system pressure, frost on the evaporator, and high compressor temperature can also be symptoms related to refrigerant issues, they do not specifically point to a leak. Low system pressure may result from a leak but might also occur due to other conditions or undercharging of the system. Frost on the evaporator could indicate low refrigerant levels due to various factors, including system inefficiencies or insufficient airflow. High compressor temperature, on the other hand, can be caused by various operational issues that may not necessarily involve a refrigerant leak but instead relate to the overall system performance and conditions. Thus, identifying traces of oil is a more direct indication of a refrigerant leak.