Hard water has a high concentration of mineral content, most commonly calcium and magnesium. It’s caused when groundwater travels through deposits of limestone or sediment.
Hard water in itself isn’t a health risk. It’s present in 85 percent of American homes and is usually safe to drink, but it’s not at all good for plumbing fixtures — especially water heaters.
Hard Water vs. Water Heaters
Hard water leaves mineral deposits behind wherever it goes. Limescale, a chalky deposit that primarily consists of calcium carbonate, accumulates in fixtures and appliances connected with hot water, like tea kettles and water heaters. Heat accelerates the conversion of minerals into limescale.
When it collects inside a water heater tank, limescale creates a sort of insulating layer along the inside walls. This makes it harder for heat to escape, leading to an overheating tank. That can cause leaks and water pressure spikes and shave years off the heater’s expected lifespan.
Mineral deposits and sediment can also lower a heater’s capacity and efficiency by making heating cycles longer, raising utility bills.
