H I G H P R E S S U R E P O R T A B L E F O R C E D A I R H E A T E R S E R V I C E M A N U A L
8
COMPONENT OPERATION
All Systems Working Together
There are four basic systems within the
heater: the fuel system, the air system, the
ignition system, and the flame control sys-
tem.
The Fuel System: The fuel pump pulls fuel
from the fuel tank and pressurizes it. The fuel
pump pushes fuel through a filter and a
solenoid valve and out the burner head
nozzle. A fine mist of fuel is sprayed into the
combustion chamber.
The Air System: The motor turns the fan.
The fan pushes air into and around the
4
S E C T I O N
FUEL SYSTEM
Fuel Pump
The fuel pump is a single stage gear-type
pump designed for two-pipe usage. The term
“two-pipe usage” means that provisions must
be made to return excess fuel from the pump
back to supply tank. Figure 1 shows position
of pump on heater.
The fuel pump is directly connected to motor
shaft. When motor on heater runs, the fuel
pump starts working. The fuel pump draws
fuel into one of the ports marked “INLETS.”
After fuel pump draws fuel into INLET port,
the fuel is then pressurized in the pump. The
fuel pump then forces fuel to the burner head
nozzle thru the port marked NOZZLE.
The port marked “PRESS ADJ” contains an
adjustment screw. Turning this screw will
increase or decrease the fuel pump pres-
sure. Check fuel pump pressure by attaching
high pressure gauge into the port marked
“GAGE.”
As mentioned above, the port marked “RE-
TURN” is used to return excess fuel back to
supply tank.
Be careful when working on fuel pump. Fuel
pump operates under high pressure.
Figure 1 - Fuel Pump
PUMP
MODEL
PRESSURE
350,000 BTU/Hr.
100 psi
600,000 BTU/Hr.
110 psi
combustion chamber. The air that goes into
the combustion chamber mixes with the fuel
for combustion. The air is heated and pro-
vides a stream of clean, hot air.
The Ignition System: The transformer sends
voltage to the spark plug. The spark plug
ignites the fuel and air mixture.
The Flame Control System: This system
causes the heater to shut down if the flame
goes out. It also allows the fan to continue
running after normal shutdown of heater.
This cools the combustion chamber.
