International Compliance Association (ICA) Home Inspector Practice Exam

What commonly causes noise in a water heater tank?

1. Air bubbles

2. Mineral buildup

3. Heating element malfunction

4. Sediment accumulation

The correct answer is: Sediment accumulation

Noise in a water heater tank is commonly caused by sediment accumulation. Over time, minerals from hard water can settle at the bottom of the tank, leading to a layer of sediment. When the heating element operates, it can cause the trapped water below the sediment layer to heat rapidly, creating steam bubbles. As these bubbles rise through the sediment, they can create popping or rumbling noises. This accumulation of sediment not only contributes to noise but can also affect the efficiency and lifespan of the water heater. Regular maintenance, such as flushing the tank, can help mitigate this issue and prevent sediment buildup, which can lead to further complications like overheating and damage to the heater. While other factors like air bubbles or issues with the heating element can cause noise, they are less common compared to the pervasive impact of sediment accumulating within the tank. As such, understanding the role of sediment is vital for effective water heater maintenance and operation.