CleaverBrooks FLX 1000, Operation, Service And Parts Manual

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Profire V Burner Chapter 2
750-177 2-5
OPERATION: Fuel oil is delivered to the fuel pump, either by gravity, fuel pump suction, or by a circulating
pump, through a fuel oil filter. Pressurized fuel returns to the storage tank until the two solenoid valves open.
Straight oil burners (VL13-55) employ direct spark ignition where the oil is ignited when the oil solenoid valves
open and the spray contacts the electrical discharge from the direct spark electrodes.
Gas-oil VLG burners use a proven gas pilot where the oil is ignited when the oil solenoid valves open and the
oil spray contacts the established gas pilot flame.
On full modulation units, the modulating actuator varies the oil metering valve setting. The metering valve
located in the return oil loop reduces the firing rate by opening and allowing more oil to return to the supply
tank. Conversely, at high fire, the valve is closed, forcing all oil to exit the spray nozzle.
On LHL units, bypass piping routes most of the oil back to the storage tank while at low fire. At high fire, a
valve blocks the return loop and forces all the oil through the nozzle.
MODULATING
MOTOR
FUEL UNIT
PRESSURE TAP
FUEL UNIT
OIL
METERING
VALVE
OIL
NOZZLE
OIL RETURN
TO TANK
OIL
PRESSURE
SWITCH
OIL SUPPLY
656-10211-000
Figure 2-2: Full Modulation Oil System with Integral Pump & Simplex Nozzle (V13-34)