What factor can lead to increased fuel consumption in an APU?

Increased load demand from connected systems can lead to higher fuel consumption in an Auxiliary Power Unit (APU). When the load demand rises, the APU has to work harder to provide the necessary power and maintain operational efficiency. This results in an increase in fuel consumption because the engine requires more fuel to generate the additional energy needed to support the increased demand.

An APU is designed to operate efficiently under various load conditions, but it has its limits. When those limits are approached or exceeded, the engine must compensate by consuming more fuel to meet the required output. In contrast, a lower ambient temperature may affect performance by increasing fuel consumption due to lower thermal efficiency, while reduced load often leads to lower fuel consumption. Regular maintenance procedures generally help ensure optimal performance and fuel efficiency, so they do not typically contribute to increased fuel consumption in the context of load demand.