How many D-pressure indicators are located on the APU?

The APU, or Auxiliary Power Unit, is equipped with two D-pressure indicators that are crucial for monitoring the operational pressure of the system. These indicators serve to provide real-time data about the fuel and oil pressures within the APU, ensuring that the parameters remain within safe operational limits. Monitoring these pressure levels is essential for the safe and efficient operation of the APU, as they help identify any potential issues or malfunctions early on. Having two indicators allows for redundancy and enhances reliability, ensuring that pilots and maintenance personnel have accurate information to make informed decisions regarding the APU's performance.