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Impact on energy consumption
Domestic energy consumption
The Government estimates that 84 per cent of the average home’s total annual energy consumption goes on heating.
This equates to approximately 23,000 KWh at a cost of approximately £1,250. Much of this involves domestic boilers heating water to use directly and to fill central heating systems.
How limescale reduces your energy efficiency
In hard water areas, limescale can build up on the water side of the boiler’s heat exchanger. This creates an insulating layer, inhibiting heat transfer to the water. Limescale builds in hard water conditions at a rate of about 1mm a year.
British Water calculate that every 1.6mm or 1/16” of scale in a heating system causes a 12% loss in heating efficiency.
The Carbon Trust, which advises on energy efficiency, report similar findings;
“A 1mm layer of limescale will cause a 7% increase in energy input to the boiler to meet the same heat demand”