The answer to 'water heater making noise' is that a noisy water heater is often caused by sediment buildup or mineral deposits on the tank's heating elements. This can lead to rumbling, popping, or banging sounds as the water heats up. Other common causes include a worn-out anode rod or a problem with the water pressure or temperature settings.
If the noises are mild and intermittent, you may be able to address the issue yourself by flushing the tank to remove sediment. However, if the noises are persistent or getting louder, it's best to call in a professional HVAC technician to diagnose and repair the issue. They can properly inspect the water heater, clean or replace components as needed, and ensure the system is operating safely and efficiently.