Block 2 - Commission Fuel Train Components & ICI Burners Self Assessment Flashcards
According to ASME CSD1, where is the installation of a strainer recommended in the gas train?
Before the horizontal components
How are oil burner valve trains different from gas fuel valve trains?
Oil valve trains often combine components into an “oil block”
Where should a high gas pressure safety device be installed according to B149.3 clause 12.5.1?
Downstream of the pressure regulator
What is the purpose of the low gas pressure safety device according to B149.3 clause 12.5.2?
To initiate shut off of the gas supply if pressure drops below 50% of the lowest normal operating pressure
How is fuel adjusted on a burner with a fuel cam?
By changing the position of the input flow control valve
Which type of VPS uses a pump and advanced instrumentation?
Active VPS
What should be checked to ensure gas-tightness of the valve seats according to B149.3 clause 15.1?
1) Appliance shutoff valve
2) Test firing valves
3) SSOV valves
What is the purpose of the overtravel linkage on a fuel cam system?
To set and lock high fire and low fire stops
What is the first step when checking the tightness of closure of a fuel valve?
Install a manometer or pressure gauge
Which clause in B149.3 specifies the outlet pressure maintenance capability of a pressure regulator?
Clause 4.4
What is a suitable option for selecting overpressure protection (OPP) when high inlet pressure is encountered?
Monitor regulation
What is the required accuracy of a pressure regulator outlet pressure during burner operation?
Within 10% above or below the regulator set pressure
When adjusting a flow control valve, what tool should be used to ensure accurate adjustments?
Combustion analyzer
For appliances with inputs in excess of 400,000 Btu/h (120 kW), where should a low gas pressure safety device be installed?
Downstream of the pressure regulator and upstream of the safety shutoff valve
What is a common feature of the SSOVs in oil burner valve trains?
Normally closed solenoid valves piped in series and wired in parallel
Which system allows precise adjustment to a single valve or damper position without affecting other components?
Parallel Position system (FARC)
What action is recommended if a fuel valve leakage is detected?
Correct any conditions causing leakage
What is the purpose of the B149.3 Annex A procedure?
To ensure safe start-up of high input gas-fired equipment
Which type of valve shall be of the quarter-turn type according to B149.3 - 6.2?
Test firing valve
What does a modern unified valve combine into a single device?**
1) Pressure regulation
2) Valve closing
3) Variable flow rate and pressure switch
What is the opening time for electro-hydraulic SSOVs?
13 seconds or 23 seconds
What is the purpose of the Proof of Closure switch?
To prove the valve is in the closed position
What is the purpose of the FGR flow control damper?
To regulate the quantity of flue gas to the FGR inlet box
When setting FGR rates, why are two emissions analyzers required?
To measure the stack O2 levels, CO, NOx emissions, and oxygen content in the burner housing
What is the purpose of the FGR flow control damper?
To regulate the quantity of flue gas to the FGR inlet box
How should the draft be adjusted if it is too low during commissioning?
Add weight to the damper chain to choke dilution air and increase draft
What is primary air in the context of combustion?
The air supplied to achieve stoichiometric combustion
Why is it important to insulate the duct, FGR damper, and inlet box assembly?
To prevent accidental burns in high-temperature areas
What is the purpose of adjusting fan speed during combustion optimization?
To find the optimal point where combustion is efficient and stable
What is the role of the PID gain settings in an integrated or standalone draft control system?
To adjust for the correct draft and set response and accuracy if modulating
Why is it important to have provisions to drain condensate in the FGR system?
To prevent water vapor accumulation and condensation in low points
How should the stack temperature switch be set during FGR system start-up?
A few degrees below the normal low fire stack temperature (approximately 200°F)
What effect does a positive combustion chamber pressure have on the system?
Adds a closing force on the regulator, upsetting control of the system
What should be confirmed before operating the burner for an extended period?
The FGR blower is in operation
What is the primary function of the FGR inlet box?
To pull flue gas from the stack and deliver it to the combustion air fan inlet
What should be the maximum pressure drop between the stack and burner inlet in the FGR ductwork?
1-inch w.c.
What should be tested and set to correct settings during operating and limit controls check?
All operating and limit controls
What should be confirmed before performing a combustion analysis?
Drafts for the appliance are correct
What should be done if the low fire light off position results in noticeable physical vibration of the equipment?
Decrease the burner firing rate
When setting FGR rates, why are two emissions analyzers required?
To measure the stack O2 levels, CO, NOx emissions, and oxygen content in the burner housing
What should be done if the low fire light off position results in noticeable physical vibration of the equipment?
Decrease the burner firing rate
What should be done if temperature and pressure variations in the boiler room prevent repeatable operation of the burner?
Add control components such as oxygen trim
What should be done if clocking is not possible due to other appliances firing?
Install an orifice plate
Why is an impulse line used in combustion systems?
To connect the combustion chamber to the air/gas ratio regulator, correcting regulator action
What is the main goal when setting the high fire air/gas ratio in a zero governor system?
To achieve the correct high fire setting using a limiting orifice
What is the function of the FGR duct temperature switch?
To shut down the burner if duct temperature exceeds the set point
Why is it important to perform a pilot turn down test?
To ensure the smallest pilot flame will ignite the main flame safely
What should be confirmed before showing up on-site for commissioning an appliance?
All appropriate permits are in order
Why is it important to note the stack temperatures during commissioning?
To compare them to the manufacturer’s specifications
Why is it important to insulate the duct, FGR damper, and inlet box assembly?
To prevent accidental burns in high-temperature areas
How should FGR damper position adjustments be made, especially at low firing rates?
In very small increments while observing readings and burner operation
What should be the maximum pressure drop between the stack and burner inlet in the FGR ductwork?
1-inch w.c.
What should be done if temperature and pressure variations in the boiler room prevent repeatable operation of the burner?
Add control components such as oxygen trim
Why is it essential to prove the stack damper is open before allowing the combustion air blower to start?
To ensure safety and proper operation of the system during the purge sequence
What information does a gas safety officer need to check permits?
Customer name, company site name, and address
What should be confirmed before operating the burner for an extended period?
The FGR blower is in operation
How should the air damper position be adjusted if the system uses linkages?
Adjust in increments of 10% using a potentiometer
What is the function of the FGR duct temperature switch?
To shut down the burner if duct temperature exceeds the set point
How should initial airflow be set during commissioning?
By adjusting the air damper(s) or fan speed
How should the stack temperature switch be set during FGR system start-up?
A few degrees below the normal low fire stack temperature (approximately 200°F)
When adjusting initial damper positions, why is it important to follow the manufacturer’s recommendations?
To achieve proper air-fuel mixing and combustion stability
What is the primary function of the FGR inlet box?
To pull flue gas from the stack and deliver it to the combustion air fan inlet
What should be checked during a site visit ahead of time?
Gas piping size, pressure, and testing
Why is it important to have provisions to drain condensate in the FGR system?
To prevent water vapor accumulation and condensation in low points
How should FGR damper position adjustments be made, especially at low firing rates?
In very small increments while observing readings and burner operation
Which of the following should be verified with gas firing valves closed?**
Prove high fire purge
