What is Scale or Limescale?
Limescale (or Calcium Scale) is a solid, off-white chalky material frequently seen on the metallic parts of water-operated equipment. It is mostly common in machinery and equipment that contains heating elements (such as boilers) or heat transfer elements (such as heat exchangers).
Limescale can also be seen in metal pipes, pumps, filters and other water equipment to a lesser or greater degree, contingent upon water quality.
The increase of this scale, which occurs over time, can brutally impede the efficiency and dependability of machinery, pipework and processes, ultimately producing a reduction in efficiency and costly breakdowns.
Where does Limescale come from?
Limescale deposits (usually referred to as “scale”) are produced by small amounts of naturally occurring minerals found in most tap water supplies. Under the right circumstances, these minerals form deposits of Calcium Carbonate, Magnesium Hydroxide and Calcium Sulphate to metal surfaces.
When water contains higher concentrations of Calcium Carbonate, Magnesium Hydroxide and Calcium Sulphate it is known as “hard water”.
Hard Water in Australia
The hardness of water varies greatly from region to region in Australia. Measured in parts-per-million the Australian Water Association has discovered ranges of 10ppm to 226ppm across the capital cities.
Commercial Impacts of Limescale
When Limescale builds up inside machinery and water equipment it slowly reduces performance outputs. Because this reduction in performance doesn’t happen all at once but slowly, over a period of time, these changes usually go undetected until it’s too late, concluding in long term losses of efficiency that persevere for long periods.
When Limescale builds up on heat transfer surfaces it acts as an insulator, decreasing the effectiveness of heat transfer. In heating applications this results in increased energy usage and additional loading on heating elements. In cooling equipment there may be a noticeable increase in thermal stress due to ineffectual cooling which can result in a reduction in efficiency and greater failure rates.
If left unchecked, pipes and pumps with Limescale deposits experience diminished water flow as the scale build up constricts critical openings. Over time Limescale can reduce flow in even large diameter pipes to a mere trickle or even block flow entirely.