2-13. OPERATION OF AUXILIARY EQUIPMENT-Continued.
Hold PREHEAT switch (4) down for: 20 seconds if temperature is above 55°F (13°C) or 1 minute
if it is below 55°F (13oC).
In extremely cold weather (32 to -25°F [0 to -32°C]), see paragraph 2-16b for cold
weather starting instructions.
Turn START switch (5) to ON and hold until engine starts. If engine does not start in 1 minute,
release START switch and keep PREHEAT switch (4) down for another 20 seconds or 1 minute
and try again. If engine still does not start, troubleshoot (see tab. 3-1).
When engine starts, release two switches (4 and 5).
If LOW OIL PRESSURE light (3) stays on after engine starts or comes on while
engine is running, Turn FUEL SHUTOFF switch (2) to OFF. Stop APU and
Let APU warm up for 3 minutes before turning on generator switch or operating the auxiliary
· Do not run APU for longer than 1 hour with generator or hydraulics engaged in
a heavy load condition. After 1 hour, turn off auxiliary generator or hydraulic
system. Run engine to allow it to cool before engaging hydraulics or generator
If HIGH AIR TEMP light (6) comes on during operation, turn off APU and let it
cool. If light comes on often, notify unit maintenance.
While APU is operating, frequently check APU CONTROL BOX for possible malfunctions.
To stop, turn APU GEN and FUEL SHUTOFF switches (1 and 2) to OFF.
If FUEL SHUTOFF switch (2) does not stop APU, turn MASTER switch to OFF.