In a heat pump system, what often indicates the presence of moisture that could lead to compressor failure?

The presence of ice in a heat pump system is a key indicator of moisture intrusion, which can lead to compressor failure. Ice formation typically occurs when the refrigerant is not circulating properly, often due to low refrigerant levels or a malfunction in the system that affects the evaporator coil. When moisture enters the refrigerant system, it can cause corrosion and acid formation, which can damage the compressor over time. The buildup of ice further insulates the coils, reducing efficiency and ultimately leading to potential compressor overheating and failure if the situation isn’t resolved.

While high pressure readings might suggest other problems, they don’t directly indicate moisture presence. Unusual noises could imply mechanical issues but are not specific to moisture content. Inadequate cooling might result from several different factors that don't necessarily involve moisture, such as airflow restrictions or capacity issues. Thus, the presence of ice is the most direct signal among the options that moisture is affecting the heat pump system, posing a risk to the compressor's longevity and functionality.