Burnham K2WTC - Page 98

98
107774-01 - 9/17
XII. Start-Up and Checkout (continued)
WARNING
Improper gas valve adjustments can result in unreliable operation, substantial property damage, personal
injury or loss of life due to carbon monoxide (CO) poisoning. Observe the following precautions:
• Do not attempt to adjust gas valve without a combustion analyzer.
• Each boiler is tested at the factory and adjustments to the gas valve are normally not necessary when
operating on natural gas at sea level. Before making any adjustments, make sure that the analyzer is
calibrated and that combustion readings have stabilized.
• Regulator (“offset”) screw used for low re adjustment is very sensitive. Adjust no more than 1/8 turn
before checking combustion with analyzer. Maximum total regulator adjustment is ± 1 turn from factory
setting.
To return the boiler to automatic modulation, press AUTO FIRE. Note: If the Auto Fire button is not pressed, boiler will
remaininmanualreforaround10minutes.After10minutesboilerautomaticallyreturnstoautomaticmodulation.
Atbothhighandlowre,COreadingsshouldbelessthan200PPMairfree.TypicalCO
2
and O
2
readings are shown in
Table 12.5A. Final readings should be taken with all doors and covers in place. If adjustments are needed, make them as
follows:
a)Withburnerathighre,adjustgasvalvethrottle(Fig12.4)asneededtoobtainCO
2
(or O
2
) setting shown in Table
12.5A.
• To reduce the CO
2
(increase the O
2
), turn throttle clockwise.
• To increase the CO
2
(reduce the O
2
), turn throttle counter-clockwise.
Make adjustments in increments of 1/8 to 1/4 turns and allow the boiler at least a minute to respond before making
another adjustment.
b)Withtheburneratlowre,adjustgasvalveoffsetregulator(Fig12.4)asneededtoobtainCO
2
(or O
2
) setting shown
in Table 12.5A.
• To reduce the CO
2
(increase the O
2
), turn offset regulator counter-clockwise.
• T o increase the CO
2
(reduce the O
2
), turn offset regulator clockwise.
Make adjustments in increments of no more than 1/8 turns and allow the boiler at least a minute to respond before
making another adjustment.
17) Performacheckoftheignitionsafetyshut-offdevice.Withtheburnerring,carefullyunplugtheorangeamerodwire
attheamerodusingapairofinsulatedpliers(Figure12.1).Theburnershouldshutoffimmediately.
18) Test any external limits or other controls in accordance with the manufacturer’s instructions.
19) Refer to the Operation Manual to set-up the control for the system in which the boiler is installed. Some common set-up
tasks include:
• Setting the CH temperature set-point.
• Deningthesystempumpoperation.
20) Adjusttheheatingthermostattoitsnalsetpoint.