What may occur if the APU fuel filter becomes clogged?

If the APU fuel filter becomes clogged, it can lead to fuel flow issues. A clogged filter restricts the amount of fuel that can pass through, which compromises the fuel supply needed for the APU to operate effectively. As a result, the APU may not receive adequate fuel pressure or volume, which can cause it to run inefficiently or even lead to a complete shutdown of the unit. This situation can prevent the APU from providing essential power and pneumatic services to the aircraft, highlighting the critical role of the fuel filter in maintaining proper APU functionality.