What issue can arise from an oversized air-conditioning system?

An oversized air-conditioning system creates conditions where the system cools the space too quickly, which can prevent adequate dehumidification. This is because air conditioners not only lower temperature but also remove moisture from the air as they operate. When the system runs for a very short duration — known as short-cycling — it doesn't run long enough to effectively remove humidity from the air. As a result, while the temperature might reach a desirable level quickly, the moisture content in the air remains high, leading to a humid and uncomfortable indoor environment.

Additionally, while increased energy consumption, reduced airflow across the evaporator, and increased indoor humidity may be associated consequences of an oversized system, they are secondary effects of the primary issue of inefficient dehumidification, which fundamentally impacts indoor comfort.