单选题A distorted furnace in a fire-tube auxiliary boiler may be the result of （）Afiring for extended periods in the low fire modeBoverheating, due to waterside depositsCvarying the water level above the crown sheetDcarrying excessive alkalinity in the boiler water
单选题
A distorted furnace in a fire-tube auxiliary boiler may be the result of （）
A
firing for extended periods in the low fire mode
B
overheating, due to waterside deposits
C
varying the water level above the crown sheet
D
carrying excessive alkalinity in the boiler water
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