For Hot Water Systems

Hard water affects more than 60% of England. Most commercial buildings in the South, East and Midland areas of the UK will be subject to the detrimental effects of limescale if left untreated.

Scale deposits form initially during the first test firing of a new installation, particularly when water velocity is low. High heat flux and low water volumes exaggerate the precipitation of calcium carbonate. NOTE: Suitably increased water velocities will delay, but never avoid, scaling. Limescale builds significantly in 'once through' water heaters as these heat large quantities of fresh water.

How does limescale affect heating systems?

  • Impaired operation (especially in hot water cylinders/calorifiers where limescale accumulates freely)
  • Reduced energy efficiency
  • Increased energy consumption (boiler has to run hotter for longer)
  • Boiler failure in pressurised systems due to boiler metal skin temperature rising above the boiling point of the water
  • System noise increases
  • Pumps have to work harder due to restricted water flow, leading to increased energy consumption

Limescale deposits accumulate quickly in appliances such as water heaters, immersion heaters, washing machines and sanitary fittings. Limescale accumulation could lead to downtime, higher capital replacement costs, unplanned maintenance and repairs, and the costs associated with cleaning 'visible' limescale. Sentinel Commercial combat water hardness with our advanced zinc-based electrolytic scale inhibitor technology, Sentinel KalGUARD.

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Compared to a typical sized ion-exchange commercial water softener, KalGUARD can save 920 litres of water a day and £3,398 a year on salt, delivering a ROI in around 12 months.


KalGUARD Pulse Splitter

KalGUARD Pulse Splitter