Why Your Water Heater Is Making Strange Noises

You can put off those holes you left in the wall when you took down some shelves, but when you notice noises coming from your water heater, you shouldn't ignore them. Even if you think it might be normal, call a professional to come to inspect the unit to ensure it's still operating safely. A malfunctioning water heater can be hazardous. Depending on the issue, you could be risking scalding water burns or even an explosion.

According to the National Fire Protection Agency, water heater fires account for around 10% of all house fires. That's 4,640 fires a year, and those fires cause about an average of 20 deaths. So while water heaters are a necessity within the home to enjoy hot showers and warm water to wash dishes in, it's vital to the health and safety of those within the home to inspect your water heater regularly. The professionals suggest having the system checked once a year to ensure nothing dangerous is being missed.

If you wake up in the middle of the night to banging or knocking from somewhere in the house, you might think someone is trying to break in. However, according to Smith Plumbing Service, this is the most common sound your water heater makes. Usually, a banging sound means there is a build-up of sediment within the heater, and what you're actually hearing is that sediment coming into contact with the heating element. This causes a tiny explosion to occur, and it sounds like banging or knocking from within the unit. Fortunately, this is an fixable and one that you could do yourself if you'd like. You'd simply have to drain the water heater and refill it.

Another cause of the banging, popping, or knocking sounds could mean the water heater is having a rare issue that is often called "water hammer" (via Buyers Ask). This happens when the water supply to the heater is shut off and then turned back on. The water rushes into the unit and the pipes and creates an unsafe amount of pressure. The pressure valves must be adjusted to ensure the water heater is in working order.

After talking about the potential that water heaters have to explode, it's probably quite alarming to then hear ticking coming from the unit. However, this isn't as scary as it sounds, and it's not a time bomb ticking away within your water heater. On the contrary, the ticking and tapping sounds that water heaters sometimes make for a simple fix and often mean the pressure within the pipes is a bit off (via Ricks Plumbing Service). You can adjust the pressure valves to fix this issue relatively easily. If you're not comfortable doing so, you can call a professional, and they will be happy to come by and adjust these valves. The valves can sometimes be hard to find, and if you're not exactly sure what you're doing, you might make the issue worse.

The difference between the not-so-dangerous ticking and the possibly dangerous "water hammer" is the amount the pressure is off. With the ticking, it's not too far off, but with "water hammer" noises, the pressure is dangerously off.

The cracking and hissing you might hear from a water heater can mean two different things depending on the type of water heater you have, according to Smith's Plumbing Services. This sound is typical for electric heaters, and when heard occasionally, there isn't anything to worry about or do. However, if it's a persistent cracking or hissing from an electric water heater, it could mean that there is something wrong with the heating element. This is an issue that shouldn't be ignored and could be dangerous if it is left untreated. Call a professional to come out and inspect the unit right away.

If you have an oil or gas water heater, the hissing and cracking are more than likely due to a build-up of moisture within the system. This is also not a good sign and something that should be taken seriously. Again, call a professional immediately so the problem can be fixed as soon as possible.