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單項(xiàng)選擇題

The water in an auxiliary boiler should be chemically tested daily for alkalinity and（）

A.soap hardness
B.nitrog encontent
C.chloride content
D.dissolved CO₂

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單項(xiàng)選擇題

Which of the following procedures decreases the total dissolved solids concentration in the water of an auxiliary boiler?（）

A.Hydrazine treatment of condensate
B.Frequent compounding
C.Chemical cleaning
D.Bottom blowing

單項(xiàng)選擇題

Failure of the burner flame in an auxiliary boiler would probably be a result of（）

A.water in the fuel oil
B.broken high tension leads
C.incorrect electrode setting
D.full fuel pressure at the nozzle

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