Landa PGHW series Operator's Manual page 16

Maintenance
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 fuel tank. Gasoline
is more combustible than fuel oil and could result in a
serious explosion. NEVER use crankcase or waste oil
in your burner. Fuel unit malfunction could result from
contamination.
Fuel Control System
This machine utilizes a fuel solenoid valve located on
the fuel pump to control the flow of fuel to the combus-
tion chamber. The solenoid, which is normally closed, is
activated by a flow switch when water flows through it.
When the operator releases the trigger on the spray
gun, the flow of water through the flow switch stops,
turning off the electrical 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 gives an instantaneous burn-or-no-burn situ-
ation, thereby eliminating high and low water tempera-
tures and the combustion smoke normally associated
with machines incorporating a spray gun. Periodic
inspection, to insure that the fuel solenoid valve
functions properly, is recommended. This can be done
by operating the machine and checking to see that the
burner is not firing when the spray gun is in the OFF
position.
Fuel Pressure Adjustment
To adjust fuel pressure, First install a pressure gage
into the port just after the pump fuel exit. Turn the
adjusting screw (located at the regulator port)
clockwise to increase, and counterclockwise to
decrease. Do not exceed 200 psi or lower the pressure
below 130 PSI, when checked at the post-pump
pressure port.
The fuel pressure may need to be adjusted due to
altitude. For every 500 ft altitude above sea level, the
boiling point of water goes down 1 °F. At high altitude
environments, this boiling point change may require the
heat input to be lowered so the water input does not
turn to steam earlier than at the factory settings and
activate the pressure sensors and pressure relief
equipment when the unit is operated and much higher
altitudes from factory settings or local dealer site
settings. Check with your dealer before making local
site fuel pressure adjustments.
16
Also, as ambient temperature changes seasonally, the
fuel temperature in the feed tank and air temperature
inlet can impact fuel flow. In more extreme tempera-
tures, this local-site adjustment may also require
different fuel nozzles for fuel inlet temperatures that are
at seasonal extremes (higher or lower) in locations
where the temperature changes are beyond moderate
temperatures of between 40°F and 90°F. Colder
temperatures will make for a thicker flow and less fine a
fuel spray while hotter temperatures will make for a
thinner flow a more fine spray with the same nozzle.
Consider alternate nozzle configurations from the
baseline factory-supplied nozzle for operating in such
temperature extremes if performance is not meeting
needs with air band and fuel pressure settings alone.
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.
Electrodes Setting
Gun Setting for EHASR Only
SR-Series Gage
Order Number: 8.717-379.0
Landa PGHW Operator's Manual 8.916-485.0 - Y
NOTE: When changing fuel pump, a by-pass plug
must be installed in return line port or fuel pump will
not prime.