TM 5-4520-240-14
tion, check heater operation as follows:
tion, or on an outside wall.
(6) Remove the thermostat cover and attach to the
(1) With the thermostat knob (fig. 2-2) set to less
than ambient temperature, set the ON-OFF switch to
thermostat a shielded 3-wire cable, long enough to
the ON position. The heater must not start.
reach between heater and thermostat, securing the ca-
ble ground (green) wire to one of the thermostat mount-
(2) Start heater operation (para 2-3) by setting the
thermostat knob to a temperature above ambient to
ing screws. Attach the other end of the cable to the
male connector that is shipped separately. Make sure
cause heater ignition.
the ground wire of the cable is connected to the ground
(3) Check that the blower motor starts and that the
lug of the connector (pin B). Connect the connector to
unit circulates air.
the room THERMO receptacle (4, fig. 2-1) on the heater.
(4) After warmup, check the exhaust for smoke and
control panel.
check for erratic operation. If either condition exists,
adjust the fuel adjustment needle (para 4-23a).
NOTE
(5) Check that the heater shuts off when the ther-
If the combined length of power cavble and thermostat
mostat set temperature is reached in the enclosure. If
talk does not exceed 20 feet, use 14-gage cable for
troth applications If the combined length exceeds 20
conditions permit, check that the unit cycles under con-
feet, use 12-gage cable.
trol of the room thermostat.
(6) Stop the heater by operating the control switch
(7) Prepare a dc power cord using a 3-wire cable
and the dc connector provided with the heater. The B
to OFF. If the heater is burning when the switch is
operated to OFF, the flame will go out immediately,
terminal must be negative (-) and the A terminal must
be positive ( +). Connect the ground to the C terminal.
hut the blower motor will continue to run until the heat
is purged from the burner, after which it will stop.
Connect the cable between the 28-volt dc power source
(7) Refer to Table 4-2, Troubleshooting, if the unit
and the POWER receptacle (3, fig. 2-1).
fails to operate in the required manner.
c. Initial Checkout and Adjustment. After installa-
Section II. MOVEMENT TO NEW WORKSITE
4-4. Dismantling for Movement.
e. Remove the bolts securing the heater to the base or
floor.
a. Disconnect the fuel line from the fuel inlet connec-
or.
f. Remove, drain, and reinstall the fuel bowl of the
b. Operate the heater until residual fuel is expended,
fuel strainer. Remove the fuel pump cover (2, fig. 4-11)
then place the cap on the fuel connection.
to drain the fuel pump. Reinstall cover.
c. Disconnect the exhaust pipe from the exhaust con-
g. Remove the plug from the float bowl and tip the
nection.
heater sideways to drain the fuel.
d. Remove the thermostat; disconnect the thermostat
4-5. Reinstallation after Movement.
and power cable connectors from mating receptacles on
Refer to paragraph 4-3 for installation instructions.
the control panel.
Section Ill. REPAIR PARTS, SPECIAL TOOLS, AND EQUIPMENT
4-6. Special Tools and Equipment.
Repair parts and equipment are listed and illustrated
No special tools or equipment is required.
in TM 5-4520-240-24P, Repair Parts and Special Tools
4-7. Maintenance Repair Parts.
List.
Section IV. PREVENTIVE MAINTENANCE CHECKS AND SERVICES
4-8. General.
s e r v i c e s which are allocated to organi-
the
preventive
This
lists
section
z a t i o n a l maintenance.
maintenance checks and services which
a quarterly
shall be performed on
4-9. Preventive Maintenance Checks and
and semiannually basis by organizational
Services.
includes
personnel. It
maintenance
Consult table 4-1 for a listing of the preventive mainte-
a n d expands upon the preventive mainte-
nance checks and services which are allocated to
nance services performed by operator/
organizational maintenance.
crew maintenance and includes additional
Change 3
4-3
