AIR CIRCULATION FAN
COMBUSTION CHAMBER
FLAME DETECTOR
IGNITION
/
TRANSFORMER/
BURNER ASSY
FLUE PIPE
COMBUSTION
BLOWER
GAS CONTROL VALVE
AUTOMATIC GAS VALVE
INTAKE OUTDOOR AIR
t=C> EXHAUST
AIR DAMPER
SOLENOID DAMPER
AIR PRESSURE SWITCH
Figure 1-12 ELEMENTS OF COMBUSTION SYSTEM