What can indicate an issue with a split system's indoor coil?

Ice buildup on the indoor coil of a split system is a clear indicator of an issue that needs to be addressed. This phenomenon typically occurs when the coil is not able to effectively regulate temperature and humidity within the space due to low refrigerant levels, airflow restrictions, or inadequate heat exchange. When the coil operates below the freezing point, moisture from the air can freeze on the coil's surface, leading to further complications such as reduced efficiency, potential damage to the coil itself, and the system becoming inoperable.

In contrast, while refrigerant leakage can certainly impact the indoor coil's function, it is not visually indicative as ice buildup is. Excessive noise might signal a problem in the overall system but is not specifically tied to the indoor coil as a defining issue. Incorrect thermostat settings can affect system operation but would not directly manifest as an issue observable on the indoor coil like ice buildup would. Thus, recognizing ice on the coil is crucial for diagnosing and resolving potential malfunctions in the split system efficiently.