Limescale and appliances: the real cost
Limescale acts as a thermal insulator on heating elements, so the appliance needs more time and more energy to reach the same temperature, and that extra consumption grows with the thickness of the deposit.
gelisted editorial team · Updated 15 August 2026
The short version
- Scale forms faster above 60 degrees.
- A scaled water heater can lose several years of service life.
- Replacing an element costs 90 € to 220 €.
- Setting the thermostat to 55 or 60 degrees slows scaling.
Limescale breaks nothing suddenly. It accumulates small losses until a 400 € appliance stops working five years earlier than it should.
Why it deposits
Calcium carbonate dissolved in water loses solubility as temperature rises, so it precipitates exactly where the heat is: on the element. Above 60 degrees the process accelerates noticeably. That layer insulates between the element and the water, forcing the element to run hotter to transfer the same heat, which shortens its life.
| Appliance | Part affected | Repair cost |
|---|---|---|
| Electric water heater | element and anode | 90 to 220 € |
| Boiler | heat exchanger | 150 to 500 € |
| Washing machine | element | 80 to 180 € |
| Dishwasher | element and spray arms | 90 to 200 € |
| Coffee machine | circuit and group | 60 to 150 € |
| Steam iron | steam outlet | replacement |
| Thermostatic tap | cartridge | 70 to 160 € |
| Screens and glassware | surface | regular cleaning |
The cost you do not see
Beyond repairs there are three continuous lines. Extra energy to heat the same water. Higher detergent and softener use, because hard water reduces the effectiveness of surfactants. And early replacement of appliances: a water heater that should last 12 years replaced at 8 represents an annualised extra cost of 30 € to 60 € on that appliance alone.
Measures that cost nothing to install
Lower the water heater thermostat to 55 or 60 degrees, which is sufficient and sits below the point where precipitation accelerates. Run a descaling cycle in the washing machine and dishwasher every 2 or 3 months. Descale the coffee machine when its indicator asks. And dry the shower screen after use, which prevents 80 per cent of the visible marks with no product at all.
These measures delay the problem but do not remove it: above 35 French degrees of hardness, accumulation continues.
When to move to treatment
When hardness passes 30 French degrees and elements or appliances have already been replaced for this reason. The calculation adds expected repairs, extra consumption and early replacement: in a family home with very hard water that set frequently lands between 150 € and 300 € a year, which pays for a softener costing 700 € to 1,800 € within 5 to 8 years.
Frequently asked
+Why does limescale build up on elements?
Because calcium carbonate loses solubility with heat and precipitates where the temperature is highest.
+At what temperature does it accelerate?
Above 60 degrees, which is why setting the thermostat to 55 or 60 helps.
+What does replacing an element cost?
Ninety to two hundred and twenty euros in a water heater and 80 € to 180 € in a washing machine.
+What can I do without installing anything?
Lower the thermostat, run descaling cycles every 2 or 3 months and dry the shower screen.
+When does a softener pay?
Above 30 French degrees of hardness, paying back within 5 to 8 years.
Sources
- 1Ministerio de Sanidad, Gobierno de España (August 2026)
- 2Instituto Nacional de Estadística, INE (August 2026)