单项选择题
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
单项选择题 Fins are installed on the fireside of water-tubes used in waste boiler to（）
单项选择题 A smoking burner with a pulsating flame in auxiliary boiler, is an indication that the（）
单项选择题 The correct procedure for giving an auxiliary boiler a bottom blow, is to begin（）
