3-3. Servicing Standby Heaters.
starting difficult or impossible.
b. Every two weeks, run standby heaters long enough
a. Heaters on standby which have the fuel connec-
to replace residual fuel in the fuel system of each --
tions and power connections intact must be run
periodically to prevent fuel in the lines from losing
heater to ensure that the heaters will start when they
volatility. Fuel with low volatility will make heater
Section Ill. TROUBLESHOOTING
occur, nor all tests or inspections and corrective ac-
tions. If a malfunction is not listed, or is not corrected
a. This section contains troubleshooting information
by the listed corrective actions, notify your supervisor.
for locating and correcting most of the operating prob-
lems which may develop in the space heater. Each mal-
3-5. Operator/Crew Maintenance
function is followed by a list of tests or inspections
which will help you to determine probable causes and
Refer to table 3-2 for troubleshooting which is allocated
corrective actions to take. You should perform the
to operator/crew maintenance levels.
tests/inspections and corrective actions in the order
Before you use this table, be sure you have per-
b. This manual cannot list all malfunctions that may
formed all applicable operating checks.
Table 3-2. OperatorlCrew Troubleshooting
TEST OR INSPECTION
1. HEATER FAILS TO START (NO FLAME, NO BLOWER).
Step 1. Clink that power is applied to heater.
Connect heater to a source of 28-vdc power. Ensure that power is connected to the POWER receptacle.
Step 2. Check that ON-OFF switch is ON.
Turn switch on.
Step 3. Check room thermostat setting.
Thermostat setting must be higher than ambient temperature of enclosure to start heater operation.
Step 4. Check RESET switch.
Press RESET switch to reset heater circuit. Start heater in normal manner.
2. HEATER FAILS TO START (NO HEAT; BLOWER RUNS FOR A SHORT TIME, THEN STOPS).
Step 1. Check that fuel tank contains fuel.
Replenish fuel supply.
Step 2. Check that fuel supply has recently been replenished and that it contains no visible contaminant,
Replace fuel in lines and tank if it has become old or contaminated.
3. HEATER OVERHEATS.
Check for airflow restrictions.
Clear area of obstructions to permit free passage of air into and out of heater.
Section IV. MAINTENANCE PROCEDURES
3-6. Maintenance of Fuel Supply.
it is important to keep the fuel tank full to prevent con-
densation in the tank. Moisture in the tank can enter
a. The heater will operate satisfactorily on any
gasoline conforming to Specification MIL-G-3056, VV-
the heater fuel system and interfere with proper com-
bustion, or can freeze in the fuel line, stopping the flow
G-76, or any other gasoline (leaded or aromatic) of up to
100-octane grade. It will also burn diesel fuel which
conforms to Specification VV-F-800, Class DF-1, DF-2,
3-7. Maintenance of Fuel Lines.
or DF-A, having a cloud point of not less than -55°F
Check that the fuel lines and fittings between the fuel
(-48°C). Aircraft turbine fuels JP-4 and JP-5, conform-
supply and the heater are not kinked, leaking, or other-
ing to Specification MIL-T-5624, will also operate this
wise damaged. Report leaks and other damage to
b. During operation in extremely cold temperatures