A.O. Smith XB-1000 Instruction Manual page 43

ADJUSTMENT
There must be sufficient load to operate the boiler at high fire to
perform the following adjustments. Start the boiler and observe
proper operating parameters for the system.
Required Tools:
• TORX T40 or 5 mm hex wrench
®
• 3 mm or 7/64 inch hex wrench
• Combustion analyzer
These boilers are equipped with a combined gas/air control
and gas safety shut off control valves. The valve functions in
parallel with the variable speed combustion blower to supply
the correct gas air ratio for optimum performance and efficiency.
The combustion blower speed is controlled automatically and
determines the amount of negative pressure experienced by the
gas safety shut off/control valves. The gas/air regulator adjusts
gas flow to maintain the proper pressure at the outlet nozzle of
the associated valve.
SETTING OF THE TEST MODE
On the Burner Home screen, select any individual boiler which
will guide to Burner Information screen.
FIGURE 43. BURNER HOME SCREEN
FIGURE 44. BURNER INFORMATION SCREEN
Click on Operation button, and under the Modulation Menu, set
the required Firing rate (High/Low) by setting the RPM.
FIGURE 45. OPERATION SCREEN
On the Firing Rate page, set the Firing rate RPM by selecting the
Manual in Run check box.
FIGURE 46. FIRING RATE PAGE
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