Which of the following would be a sign of a malfunction in a refrigeration system?

A sign of a malfunction in a refrigeration system is often indicated by unusual noises coming from the compressor. The compressor is a critical component of the refrigeration cycle, and if it is functioning improperly, it may produce sounds that are not typical of normal operation. These noises can signal various issues, such as mechanical failure, refrigerant issues, or problems with other components in the system.

For instance, if the compressor is making grinding, rattling, or squealing sounds, it could indicate that parts are worn or damaged, or that there is a problem with the lubricant level. Addressing these unusual sounds promptly can prevent more significant issues from developing, ensuring the longevity of the refrigeration system.

In contrast, constant temperature readings, efficiency improvements, and reduced power consumption do not usually indicate a malfunction. Consistent temperature readings could suggest that the system is operating effectively, while efficiency improvements and reduced power consumption are likely signs of an optimized or better-functioning system. Hence, unusual noises from the compressor stand out as a clear indicator of potential malfunction.