water, steam, and electrical) vary with different types and kinds of boil ers. Always follow the manufacturer's instructions for the boiler being used. Before lining up a boiler, complete the following basic tasks:
1. Fuel oil
a. Measure with a stick or gauge.
b. See that the proper valves are open.
c. Remove any excess accumulation of water in the tank.
2. Gas
a. Check the pressure.
b. Check for leaks.
3. Gas-fired unit
a. Check and regulate the water level and line up the feed system.
b. Examine the burner, control valves, and safety shutouts for proper working condition before lighting off.
c. Purge air out of the gas lines by external vents before lighting off.
d. Check the draft devices and purge the combustion chamber.
e. Light the pilot and set the flame.
f. Open the main gas cock.
g. Close the burner controls switches to light the burner.
h. Maintain the fuel-air ratio for complete combustion.
4. Oil-fired unit
a. Check and regulate the water level. Line up the feedwater system. Check the operation of the feed pump.
b. Line up the fuel oil system.
c. Purge the combustion chamber.
d. Close the burner control switch; if automatic, the burner should light off.
e. Should ignition fail, the furnace must be purged before a second attempt is made.
f. Do not allow oil to impinge on brickwork or part of the boiler.
g. Maintain the proper air-fuel ratio.
In general, the basic lighting off procedures for most boilers are as follows:
1. Close the following valves:
a. All blowdown valves and boiler drains.
b. Chemical feed valves.
c. Boiler nonreturn.
d. Main steam stops.
e. Soot blower header (steam system) and all soot blowers.
f. All burner fuel valves.
g. Water column and feedwater regulator drains.
h. Auxiliary valves, as necessary.
2. Open the following valves:
a. Vent valves on boiler drums and superheaters.
b. Superheater drain valves.
C. Recirculating line valves in economizer, if so fitted.
d. Feedwater stop and check.
e. Drum steam gauge connection.
f. Water column gauge connections.
g. Water column gauge glass valves.
h. Auxiliary valves, as necessary.
3 . Start filling the boiler with properly treated water at a temperature close to the temperature of the pressure parts. The temperature difference should not be greater than 50F to avoid severe temperature stresses. Fill the boiler to level just below the middle of the glass on the water column.
4. Close the induced draft fan dampers (or other flue gas control dampers).
5. Start the induced draft fan.
6. Close the forced draft fan dampers (or other air control dampers).
7. Start the forced draft fan.
8. Start the air heater rotor, if a regenerative type of air heater is installed.
9. Light off the boiler under the manufacturer's instructions and maintain a firing rate so the water temperature in the boiler is raised 100F per hour until operating pressure is reached. On
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