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Sookook Corporation
2D. Commissioning Adjustment
Conduct the commissioning according to the followings.
a) Make sure the manual shutoff valve is open.
b) Check that the gas supply pressure is correct.
c) If the burner does not start even after the burner operation switch is turned on, check that the burner controller is not locked out (Red
light, 2E, See burner controller). At lock-out, the burner will not start unless reset.
d) Check whether the boiler's temperature or governor is closed. (Check the interlock.)
e) When burner is started, fan motor starts and pre-purge begins. If the burner controller operates the damper motor in the open direction
to for pre-purge at the maximum air flow rate, the air damper connected to the damper motor and linkage device is opened to the
maximum, and the pre-purge is performed for about 30 seconds at this position. At the end of the pre-purge, the air damper closes to
the set ignition position and proceeds with ignition. At this time, if the damper motor is not closed below the setting value of high
combustion ignition prevention limit, the ignition is not performed and locked out. The ignition is operated when the power is applied to
the ignition transformer and 1 second later, the power is applied to the gas safety shutoff valve and the valve opens. The ignition
transformer runs for 5 seconds and shuts off.
f) When the ignition is completed, the sequence control is completed and the burner controller will start the load operation thereafter. If the
ignition fails, the burner will stop and be locked out.
g) If the burner is operating normally, adjust the gas flow required for each load and the combustion air flow rate accordingly. Be sure to
install an exhaust gas analyzer in the gas duct to adjust the flow rate while analyzing the exhaust gas in real time.
During adjustment at commissioning, it’s better to reduce the air flow from excess state than to increase from insufficient state to adjust to a
proper air ratio. There is a risk of carbon monoxide if the air is running low. If this happens, immediately restart the burner to purge the carbon
monoxide in the combustion chamber. To maintain a stable combustion condition, adjust the gas and air flow while checking the followings.
ⅰ) Does ignition and combustion proceed without backfire?
ⅱ) Are there any catching or vibrational combustion during ignition or combustion?
ⅲ) Is it the optimum combustion state?
(If the load is lower than 50%, O2 is recommended to be lower than 5% and if the load is over 50%, O2 is recommended to be lower
than 4%. At all load factor, CO concentration shall be below 100ppm.)
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