What can contribute to ice buildup in the evaporator unit?

Ice buildup in the evaporator unit is primarily related to airflow and refrigerant levels. When there is restricted airflow, it can prevent the warm air from adequately circulating over the evaporator coil, which is necessary for the coil to absorb heat and maintain the proper temperature. If the airflow is insufficient, condensation can accumulate and eventually freeze, leading to ice buildup.

Similarly, low refrigerant levels can lead to insufficient absorption of heat by the evaporator coil. This condition results in lower temperatures in the coil, increasing the likelihood of moisture freezing on its surface. Without the proper level of refrigerant, the cooling system is unable to operate efficiently, contributing to the formation of ice.

In contrast, high refrigerant levels and excessive lubricants do not directly contribute to ice formation in the same way. High refrigerant levels can cause other issues, such as flooding the evaporator, but ice formation is more closely linked to airflow restrictions and inadequate refrigerant. Additionally, high ambient temperatures typically increase the cooling load, making ice buildup less likely unless paired with other issues like restricted airflow.