Accumulated condensate can lead to noisy and damaging water hammer resulting in leaks in the steam system that wastes energy. To reduce the possibility of leaks, drain condensate at regular intervals.
As steam loses heat, it turns back into water. Steam inevitably begins to do this as soon as it leaves the boiler. This water known as condensate does not transmit heat effectively, reducing steam's heat transfer potential.
If condensate is allowed to accumulate the overall effective cross sectional area of the pipe also reduces. This causes steam velocity to increase above the recommended limits. The mixture of steam and condensate at high velocities is damaging as it leads to erosion and water-hammer.
Water-hammer is the phenomenon caused by slugs of condensate colliding at high velocity into pipework fittings, and equipment. The resulting erosion and corrosion of the pipework and equipments create leaks in the steam system. Reduced leakage automatically leads to reduced steam consumption and thus a lower fuel bill.
Fig: The slug of condensate is carried along the pipe length and collides with pipe walls at bends or pipework fittings leading to erosion.