OPERATE AUXILIARY POWER UNIT -- CONTINUED
STARTING APU -- CONTINUED
7. Set APU GEN switch (5) to OFF.
8. Set FUEL SHUTOFF switch (6) ON.
The LOW OIL PRESSURE indicator will light and stay on until the APU is running.
The PREHEAT switch is held up until the APU starts.
9. Hold the PREHEAT switch (7) up for 20 seconds (for temperatures above 55° F (13° C)) or for 1 minute (for
temperatures below 55° F (13° C)).
10. Move START switch (8) to ON and hold until engine starts. If engine doesnt start in 1 minute, release the START
switch and keep the PREHEAT switch up for another 20 seconds (or 1 minute below 55° F(13° C)). Try starting
APU again. If it still doesnt start, troubleshoot (WP 0083 00).
If LOW OIL PRESSURE indicator stays on after the APU starts, or comes on while APU is
running, turn FUEL SHUTOFF switch to OFF to stop APU. Failure to comply may result in
failure of the APU.
11. When the APU starts, release both the PREHEAT and START switches.
12. Let APU warm up for three to five minutes before turning on the APU GEN switch (5) or operating the auxiliary