Cleaver-Brooks CBH 40 - Page 15

representative should adjust or
repair these valves.
COMBUSTION AIR PROVING SWITCH
(Figure 1-1)
A
pressure sensitive switch, actuated by air pres-
sure, whose contacts close to prove sufficient pres-
sure of combustion air from the forced draft fan.
OIL PUMP (Figure 1-1)
Draws oil from supply tank and delivers it under
pressure to the burner nozzles. The pump contains
an integral adjustable pressure regulator and
rotary filter. The pump is driven by a V -belt con-
nected to the blower motor.
OIL BURNER PRESSURE GAUGE (Figure 1-1)
Indicates the fuel pump discharge pressure to noz-
zle.
FUEL OIL VALVES (Figures 1-1 & 1-6)
Electrically operated to open in a controlled se-
quence to allow oil flow from the pump to the bur-
ner nozzles. The function of the valves is described
INTERMEDIATE
FRONT
HEAD
HEAD
GASKET
Chapter !-General Description and Principles of Operation
in the oil fuel flow section later in this chapter.
FUEL OIL SHUT-OFF COCK (Figure 1-1)
For manually shutting off oil supply to burner.
LOW OIL PRESSURE SWITCH (Optional)
(Figure 1-3)
Switch contacts open when fuel oil pressure drops
below selected pressure. Switch will interrupt the
limit circuit upon loss of sufficient fuel oil pressure
for correct combustion.
AIR DAMPER (Figure 1-5)
Controls the amount of combustion air admitted to
the burner in proper proportion to fuel input for ef-
ficient combustion at high or low firing rates.
NOTE: Depending upon the requirements of
the insurance carrier or other governing agen-
cies, the gas flow control system, or gas train,
may consist of some, or all, of the following
items. Refer to your boiler to determine those
that are applicable. A typical gas train is
shown in figure 1-4.
AIR BAFFLE
PLATE
NOTE: Burner shown in place for illus-
tration purposes only. Burner drawer
must be removed prior to opening
head.
FIGURE 1-5. BOILER WITH FRONT HEAD OPEN, CBH 50-100A OIL AND GAS FIRED
1-7