CleaverBrooks FLX Operation, Service And Parts Manual page 14

Chapter 2
transformer is powered, and pilot valve is energized
(open).
c. MAIN FUEL (green) - Illuminates when the main
fuel valve or valves are energized (open).
d. FLAME FAILURE (red) - Illuminates when the
flame safeguard system fails to detect pilot or main
flame.
7. MODULATING MOTOR
Operates the air damper and fuel rate valves through a
linkage system to adjust air-fuel ratios under all load
conditions.
8. IGNITION TRANSFORMER
Provides high voltage spark for ignition of gas pilot or
main flame direct spark models.
FLAME SAFEGUARD CONTROLS
The flame safeguard controls the operating sequence of the
combustion system (pre-purge, pilot, firing, and shutdown).
The flame safeguard programmer incorporates a flame
sensing cell (scanner) to shut down the burner in the event of
pilot flame or main flame failure. Other safety controls shut
down the burner based on sequence of operation as shown in
the manufacturer's flame safeguard manual.
When a parallel positioning system is furnished, the flame
safeguard may be incorporated as an integral component to
the parallel positioning control. Consult burner and
component technical documentation.
COMBUSTION AIR HANDLING SYSTEM
1. MOTOR AND BLOWER
The impeller is directly driven by the motor at 3450 rpm. A
heavy duty forward curved, multi-blade centrifugal impeller
supplies combustion air.
2. AIR VOLUME REGULATOR
Air dampers are located in the air inlet housing. The dampers
are mechanically linked and actuated by a two-position motor
or hydraulic cylinder for on-off operation. Low-high-off,
low-high-low, or full modulation burners have the dampers
mechanically linked to the modulating motor.
3. COMBUSTION AIR PROVING SWITCH
A pressure sensitive, differential switch actuated by air
pressure created by the blower fan. Contacts close to prove
combustion air flow.
4. DIFFUSER
An air flow diffuser stabilizes flame front.
OPERATION: Air from the impeller flows through the blast
tube and diffuser to mix with fuel in the ignition zone.
Combustion air flow rate is determined by the position of the
air regulating blades at the inlet of the impeller. Linking the
2-2
air flow with the fuel flow provides efficient combustion at all
firing rates.
OIL SYSTEM
Models Vl-VLG are high pressure atomizing burners using
fuel pressure for atomization. Atomized fuel is discharged
from the nozzle as a fine conical spray.
1. FUEL UNIT - Size 1 & 2
Direct driven from the blower motor with a flexible coupling
at 3450 rpm, and set for 300 psi operation, fuel unit is two
stage (two sets of gears) and must be installed for a two pipe
installation, one suction and one return line. Separately
driven oil pumps are available as options to the standard
arrangement.
Size 3 & 4
A separately driven oil pump is standard.
2. NOZZLE
The nozzle meters oil flow delivering a specified amount at a
specific pressure. Fuel pressure (mechanical) atomizes oil in
A B C
a fine conical spray pattern from the nozzle orifice. The
burner is supplied with nozzle(s) to fire to its maximum rate
unless a different firing rate was specified. VL and VLG
models 13-34 supplied with simplex nozzles, models 35-168
are supplied with return flow nozzles.
3. NOZZLE ADAPTOR
The nozzle adaptor provides the means for connecting fuel
lines with the nozzle.
4. OIL SOLENOID VALVES
Two normally closed (N.C.) and one normally open (N.O.)
solenoid valves are part of the oil system on LO-HI-OFF and
LO-HI-LO burners. The two N.C. valves provide positive
shutoff of fuel oil while the one N.O. valve cycles the burner
to HI fire when closed.
5. OIL METERING VALVE
The firing rate is controlled by an adjustable metering valve
in the return line. At low fire, the metering valve is open, and
is closed at high fire.
6. OIL FILTER
Prevents foreign matter from entering the burner oil system.
This item is provided optional and shipped loose with burner.
OPERATION: Fuel oil is delivered to the fuel unit, either by
gravity, fuel unit suction, or by a circulating pump, through a
fuel oil filter. Pressurized fuel returns to the storage tank until
the two solenoid valves open. On direct spark ignited burners
(VL-13 to 55) ignition occurs when the oil valves open.
Where gas pilots are provided (models VG and VLG), the oil
valves open after the pilot is proven. Oil input rate is
controlled by the oil metering valve, which varies the flow to
Profire V Burner
D
E F G
8
750-177