Water Heater

Your water heater making noise can be normal. Because these appliances are typically tucked away in basements or utility rooms, homeowners often don’t realize the sounds they make during regular use. However, as with HVAC noises, some water heater noises indicate potential problems.

5 Common Reasons Your Water Heater’s Making Noise

Here’s a rundown of five common water heater noises and what they might mean.

1. Normal Expansion and Contraction

If your hot water heater makes noises that sound like metal popping or bending, it’s probably normal. As the tank and pipes heat up or cool down, the metal naturally expands and contracts, leading to knocking or ticking sounds.

2. Sudden Pressure Changes

Hearing a knocking sound when someone turns a hot water tap on in the home can also be normal. It may mean valves are shutting quickly, creating a bit of a “slamming door.” Though this type of sound may only indicate high water pressure, consider getting it checked out to ensure pipes and valves hold up to current use and aren’t at risk for leaks.

3. Loose Components

A common problematic reason for a water heater making noise is internal or external parts coming loose. Mountain brackets, drain valves and other parts may work loose, causing vibrating and rattling sounds. Some issues may be minor or simply annoying; others can be serious. In any case, getting professional eyes on your appliance can help you locate the source of the noise and complete water heater repairs.

4. Buildup in the Tank or on Parts

Buildup and sediment in your tank or on parts of your system can lead to odd sounds. If you have hard water, minerals can create sediment at the bottom of your tank over time. Once the sediment is thick enough, it can trap water temporarily under it. As water in the tank heats, it bubbles up through that layer of debris, which can create various sounds.

Mineral content in your water can also create scaling on heating elements. Water gets caught here too, boiling against the elements as they heat up. You may hear sizzling or popping sounds reminiscent of water or oil in a hot pan.

5. Normal Operation

Sometimes, just using hot water in your home can create noise. A water heater making a buzzing noise or humming sound may simply indicate that it’s running. Some people are more likely to hear these types of noises than others; you may hear a humming noise near your water heater if you can also regularly hear your fridge or the soft sound of electrical components running.

The bottom line regarding a water heater making noise is that loud, sudden noises or new noises may indicate a problem. If you’re unsure about whether your appliance is running well, contact HVAC professionals for peace of mind.

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