TM 9-4520-272-14&P
UNIT MAINTENANCE
LARGE CAPACITY FIELD HEATER (LCFH)
MALFUNCTION SYMPTOM INDEX
GENERAL
This chapter provides information to permit the maintainer to troubleshoot some problems that may occur
during the course of LCFH operation.
MALFUNCTION SYMPTOM INDEX
The malfunction symptom index lists common malfunctions that may occur during the operation of the
Large Capacity Field Heater. Find the malfunction to be eliminated and go to the indicated
troubleshooting table in work package 0016 00. This index cannot list all malfunctions that may occur, all
tests or inspections needed to find the fault, or all actions required to correct the fault. If the existing
malfunction is not listed, or cannot be corrected through this troubleshooting index, notify unit
maintenance.
In Table 2 below, a soft fault is defined as one in which the engine continues to operate but the burner is
fault locked out; however the heater can be reset to attempt another burner run cycle. If the burner if
running when a soft fault occurs, the heater will proceed to the post purge cycle followed by engine shut
down and fault lock out. If burner is not operating then the engine will shut down followed by a fault lock
out.
If a hard fault occurs before the burner starts or after the burner has normally cycled off (due to
temperature regulation) then the heater will not proceed to post purge and the engine will shut down.
The last ten fault codes that have been displayed on the operator control box can be displayed in reverse
order by toggling the switch labeled RESET on the operator control box front panel. This is useful in the
case of a fault code being displayed too quickly to note or if maintenance wishes to view the last several
fault codes.
Table 1. LCFH Fault Code Series Key.
Series
System Affected
100 series
Electrical
200 series
Burner
300 series
Carbon Monoxide (CO) sensor
400 series
Control panel
500 series
Engine
600 series
801
Software
Table 2. LCFH Unit Level Malfunctions
Malfunction
Troubleshooting
Step
Engine will not crank ..................................................................................................................................... 1
Engine will not start ....................................................................................................................................... 2
Engine starts and stops................................................................................................................................. 3
Engine output drops ...................................................................................................................................... 4
Engine runs rough ......................................................................................................................................... 5
Low compression pressure ........................................................................................................................... 6
Engine emits white smoke ............................................................................................................................ 7
Engine emits black smoke ............................................................................................................................ 8
0015 00-1
