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9.800-079.0 • Rev. 04/10
13
PRESSURE W
ASHER
OPERA
T
OR’S MAN
U
AL
Fuel:
Use clean fuel oil that is not contaminated with water
and debris. Replace fuel filter and drain tank every 100
hours of operation.
Use No. 1 or No. 2 Heating Oil (ASTM D306) only.
NEVER
use gasoline in your burner tank. Gasoline is
more com bus ti ble than fuel oil and a serious explo-
sion could result.
NEV ER
use crankcase or waste oil
in your burner. Fuel unit mal func tion could result from
con tam i na tion.
Fuel Control System:
These machines utilize a fuel solenoid valve located
on the fuel pump to control the flow of fuel to the com-
bus tion cham ber. This solenoid valve, which is normally
closed, is ac ti vat ed by a flow switch when water is flow-
ing through it. When an operator releases the trigger on
the spray gun, the flow of water through the flow switch
stops, turning off the current to the fuel solenoid. The
solenoid then closes, shutting off the supply of fuel to
the combustion chamber. Controlling the flow of fuel in
this way allows for an in stan ta neous burn or no burn
situation, thereby eliminating high and low water tem-
per a tures, and combustion smoke nor mal ly associated
with machines incorporating a spray gun.
CAUTION:
Periodic inspection is recommended to in-
sure that the fuel solenoid valve functions properly. This
can be done by operating the machine and checking to
see that when the trigger on the spray gun is in the off
po si tion, the burner is not firing.
Electrode Setting:
(See illustration below.)
Burner Nozzle:
Keep the tip free of surface deposits by wiping it with a
clean, solvent-saturated cloth, being careful not to plug
or enlarge the nozzle. For maximum efficiency, replace
the nozzle each season.
Air Adjustment:
Machines are preset and performance tested at the
fac to ry - el e va tion 100 feet. A one-time initial correction
for your lo ca tion will pay off in economy, performance
and ex tend ed ser vice life. If a smoking or eye-burning
ex haust is being emit ted from the stack, two things
should be checked. First, check the fuel to be certain
that ker o sene or No. 1 home heating fuel is being used.
Next, check the air ad just ment on the burner.
To adjust:
Start machine and turn burner ON. Loosen
two locking screws found in the air shutter openings
(re fer to illustration below) and close air shutter until
black smoke appears from burner exhaust vent. Note
air band position. Next, slowly open the air shutter until
white smoke just starts to appear. Turn air shutter half-
way back to the black smoke position previously noted.
Tighten locking screws.
If the desired position cannot be obtained using only
the air shutter, lock the air shutter in as close a position
Periodically check wiring connections. If necessary to
adjust electrodes, use diagram.
Top View
Side View
5/32"
1/4"
5/32"
Nozzle
Electrode
FUEL AIR ADJUSTMENT
Pressure
Gauge
Port
Pressure
Adjustment
Screw
7-00098 Fuel
Pump
To Fuel
Tank
Air Band
Air Band
Adjustment
Screw
Return Line
MAINTENANCE