Man Hours 2
Special instructions:
1. Review manufacturers instructions.
Items to Check & Initial Completion:
1. ___ Check boiler room for adequate ventilation in accordance with AGA burner
requirements.
2. ___ Check operation of all gas controls and valves including: manual gas
shutoff; petal gas regulator; safety shutoff valve (solenoid); automatic
gas valve; petal solenoid valve; butterfly gas valve, motor, and linkage
to air louver; safety petal solenoid (if used).
3. ___ Check flue connections for tight joints and minimum resistance to air
flow. (See that combustion chamber, flues, breaching, and chimney are
clear before firing.)
4. ___ Draft regulators should give slightly negative pressure in the combustion
chamber at maximum input.
5. ___ On forced draft burners, gas manifold pressure requirements should
correspond with modulating (butterfly) valve in full open position and
stable at all other firing rates.
6. ___ Take flue gas readings to determine the boiler efficiency. Use the
manufacturer's instructions if available. If they are not, use the
attached table as a guide for the performance criteria. If efficiency is
low, check baffling and passes for short circuiting, and boiler for air
infiltration. Adjust dampers and controls to optimize efficiency. Tests
should be run at the following load points.
a.___ 100%, 70%, and 40% of rated full load for boilers having metering
controls or modulation capacity at these load points.
b.___ At the high and low fire rates on boilers equipped with OFF/LOW
FIRE/HIGH FIRE control.
c.___ At the single firing load point on boilers equipped with OFF/ON
controls only.
7. ___ Check burner for flashback and tight shutoff of fuel.
8. ___ Check operation of controls. Clean and adjust, if necessary.
9. ___ Satisfactory operation and adjustments should conform with manufacturer's
instructions.
Performance Criteria for Gas Burners
Natural Gas (1,000 BTU/SCF)
Percent Load
40.0%
70.0%
100.0%
Carbon Dioxide (CO2)
8.5%
9.0%
10.0%
Carbon Monoxide (CO)
0
0
0
Oxygen (O2)
6.0%
5.0%
4.0%
Excess Air (XA)
40.0%
25.0%
20.0%
Smoke Scale No.
0
0
0
1. ___ Combustibles should be zero or negligible percent in the flue gas.
2. ___ Output (steam or water flow) where meters are available should correspond
to combustion level not less than 100% of rated capacity at rated load.
3. ___ Boiler section outlet flue gas temperature is not more than 30oF (17oC)
higher than rated. When the expected gas temperature is not known, the
manufacturer should be contacted for typical conditions for the type of
boiler being tested.
4. ___ Boiler section outlet flue gas temperature should not be more than 150oF
to 180oF (84oC to 100oC) higher than the corresponding saturated steam
temperature for water tube boilers and 100oF to 125oF (56oC to 70oC) for
firetube boilers.
5. ___ Excess air should be within 5 percent of manufacturer's performance level.
6. ___ Feedwater temperature, burner atomizing pressure, draft loss, and
combustion appearance should be in accordance with manufacturer's data or
be close to industry standards.
Tools and Materials:
1. Standard Tool kit.
Plus Pipe wrenches to 24"
Tubing cutters
Flaring tool
Small acetylene outfit
Packing tool kit and packing
3/4" socket set
Crescent wrenches to 14"
2. Flue gas analyzer.
3. Clean wiping cloths.
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