What are the problems caused in boiler using hard water?

Using hard water in boilers can lead to several problems, primarily scaling and deposit formation. The minerals in hard water, such as calcium and magnesium, accumulate on the boiler's heating surfaces, reducing heat transfer efficiency and increasing fuel consumption. This scaling can also cause overheating and potential damage to the boiler components, leading to costly repairs and increased maintenance. Additionally, hard water can contribute to corrosion, further compromising the boiler's integrity and lifespan.