TM 9-4940-556-14&P
3.7.2.1 Remove cover.
3.7.3 Remove 3/4 inch pipe plug (item 16 drawing JP7205-A) from float
tank outlet fitting assembly.
3.7.4 Install suction hose (with supplied foot valve installed) into
Tee (item 17 drawing JP7205-A).
3.7.5 Place foot valve into water source. Protect from sand, mud
or trash as much as possible.
3.7.6 Follow 3.1 and 3.2 or 3.3 as desired.
3.8 DESCRIPTION OF OPERATION AND COMPONENTS - ELECTRICAL REF. JP7200
3.8.1 Turn switch S-1 to the "ON" position. This will energize the
machine power circuit.
3.8.2 Turn switch S-2 to the "ON" position. This will energize the
motor M-1, the ignition transformer T-2 and it will drive the water
pump, air blower fuel pump.
3.8.3 Pressure switch PS-2 connected to the pump outlet before
the mechanical unloader U-1 is normally open, it will close at
100 psi.
3.8.4 Temperature control TC-1, which is located at the coil outlet,
is normally closed and will open above 360F.
3.8.5 Burner switch S-3 will open the fuel solenoid provided the pressure
switch PS-2 and temperature control TC-1 are closed. If any of these
switches open, it will reenergize the fuel solenoid and therefore terminate
the burner operation. With all the above switches closed, the burner
circuit will be energized thru the following procedure.
Time delay relay TD-1 will be energized and relay coil R-1 will
a.
be energized thru the normally closed TD-1 contact, provided
pressure switch PS-3 is closed. Pressure switch PS-3 is normally
open and will close when there is sufficient air pressure in the
air chamber.
With relay coil R-1 energized, relay contacts R-1A closes and
b.
will energize the fuel solenoid valve SV-1.
With satisfactory burner performance flame sensor FS-1 will close
c.
and will maintain the relay coil R-1 holding circuit.
After 45 seconds, time delay relay TD-1 normally closed contact
d.
will open and with the flame sensor FS-1 contact closed, the
burner circuit will remain energized. When flame sensor FS-1
opens, it will reenergize the burner circuit.
To reset burner circuit and time delay relay TD-1, open and close
e.
burner switch S-3.
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