CleaverBrooks CBLE, Operation And Maintenance Manual

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Burner Operation and Control
2-14 750-91 (revised 2009)
Model CB-LE Packaged Boiler Manual
2.7 — Controls for Combination Burners Only
Burners equipped to burn either oil or gas include equipment for each fuel. The Gas-Oil Selector Switch engages
the appropriate interlocks and controls for gas or oil operation. Chapter 4 details the required mechanical functions
of each fuel system.
Manual Bypass Valve Provided as a timer saver in establishing oil flow. When open, it per-
mits circulation of oil through the supply and return lines. The valve
MUST be closed prior to initial light off.
Orifice Oil Control Valve Valve may be opened prior to startup to aid in establishing fuel oil
flow through the controller. The valve
MUST be closed prior to
initial light off. Its disc has an orifice to permit a continuous circula-
tion of hot fuel oil through the controller.
Air Purge Valve Solenoid valve opens simultaneously with closing of oil solenoid
valve at burner shutdown, allowing compressed air to purge oil
from the burner nozzle and adjacent piping. The oil is burned by
the diminishing flame, which continues burning for approximately 4
seconds after the oil solenoid valve closes.
Air Purge Orifice Nozzle Limits purging air to proper quantity for expelling unburned oil at
normal delivery rate.
Air Purge Orifice Nozzle Filter Filters the purging air of any particles that might plug the air purge
orifice nozzle.
Air Purge Check Valve Valve check prevents fuel oil from entering the atomizing air line.
Air Purge Relay When energized, control operation of air purge valve.
Component Description