Which factor is not typically affected by high outdoor temperatures in an AC system?

High outdoor temperatures can significantly impact several operational aspects of an air conditioning system.

Cooling capacity is often reduced in high heat situations because an AC unit's ability to transfer heat can decrease as the temperature outside rises. This means the system might struggle to cool air as effectively.

System efficiency is also affected as higher ambient temperatures can lead to increased energy consumption and reduced performance because the condenser unit has to work harder to release heat.

Compressor lifespan can be impacted as well, since excessive heat can cause the compressor to overheat, leading to premature wear or potential failure.

Indoor air filtration, however, is primarily influenced by the quality of the air and amount of particulates within it, rather than the outdoor temperature. The filtration system's job is to clean the air circulating indoors, and this function does not directly correlate with how hot or cold it is outside. Therefore, the correct choice indicates that among these options, indoor air filtration remains unaffected by high outdoor temperatures.