单项选择题
The water level showing in a boiler water gauge glass is usually （） during working.
A.higher than the actual drum water level B.equal to the actual drum water level C.increasing due to steam condensation in the glass D.lower than actual drum water level
单项选择题 A dazzling white burner flame in the boiler furnace indicates （）.
单项选择题 When the boiler load returns to normal, the drum pressure will rise and steam bubble formation will reduce, causing a fall in water level This is known as （）.
单项选择题 WHR stands for （）.
