Why does the water drop first and then rise when the boiler fires?
Often in the operation of the boiler, the steam water mixture to the drum after intense evaporation of a large number of bubbles in the water side, the water volume expansion. By actual water level drum water level indicator is higher than the water level
This is the reason for the zero water level gauge line below the center line of the drum. Under normal conditions for water and evaporation is balanced, after the fire, reduce the amount of steam water mixture into the drum in the evaporation decreased rapidly, reduce the volume of water bubbles, sudden contraction, drum water level decreased rapidly. But not to water change or increase (automatic), water balance is broken, the water level will rise rapidly.
