WHAT MAKES MY WATER HEATER RUMBLE?

Calcium buildup is the common factor for this noisy problem. When super-cold water collides with super-hot water from the bottom of the water heater, an audible noise is produced, similar to that of water droplets into a hot greasy pan. Imagine your water heater as a teakettle with sediment buildup at the bottom. The water at the bottom of the teakettle is much hotter and as we learned in science class, heat rises. This is not dangerous, but is a concern and can lead to premature failure of your water heater and consumes much more energy, resulting in a higher gas/energy bill. You will also notice a decrease in available hot water.