3 Things That Can Cause Your Water Heater To Burst

Imagine you’re relaxing at home when—suddenly—your ceiling caves in; water starts flooding everywhere.

The cause? It’s not a storm; It’s that your water heater burst.

(Here’s a 1-minute video of what a water heater burst can do to your home.)

This disaster is one of the top five sources of residential water damage, according to the Insurance Institute for Business and Home Safety (IBHS), leading to an average of $4,444 per incident after the deductible was paid.

Sure, that’s scary. But will it happen to you?

If you have the following problems, your water heater could be at risk of exploding.

  1. Sediment build-up
  2. Rust corroding the tank
  3. Too much internal pressure

We'll go into more detail about each of these issues and how you can prevent them.

1) Sediment build-up

The problem: Over time, sediment (minerals from your hard water) settles at the bottom of your water heater’s tank. This mineral layer insulates the water from the burner, forcing it to run longer to heat the water, causing it to overheat and deteriorate the tank.

Image source: Bradford White

You have this problem if: Your water heater makes a popping, knocking noise. That noise is water trapped under the sediment bubbling up, trying to escape the sediment layer. It’s like how boiling water pushes up a pot’s top.

How to prevent: You need to flush and drain the tank of the sediment once a year.

2) Rust corroding the tank

The problem: Your water heater is made of steel, which is mostly iron. Meaning that over time the water will cause the tank to rust.

Thankfully, your water heater has an internal rust protection element: A “sacrificial” anode rod.

This 3-5 feet rod rusts in place of the tank (thus why it’s a “sacrificial” anode rod). But once that rod deteriorates, your water heater rusting out will follow soon after.

You have this problem if: Your hot tap water is a brown, rusty color.

How to prevent: Inspect the anode rod once every two years and at least annually once the warranty has expired. You’ll probably change the anode rod once every 4-5 years—sooner still if you have a water softener.

Watch this video on how to replace an anode rod.

3) Too much internal pressure

The problem: If you blow enough air into a balloon, what happens? POP!

The same thing happens to water heaters. If too much pressure builds in the tank, it will eventually spring a leak and burst.

And if the pressure gets really ridiculous, the tank actually explodes, becoming part bomb, part rocket.

Kaboom! Source: MythBusters

Thankfully, your water heater prevents this problem using its T&P (temperature and pressure) relief valve. It opens up, releasing some of the water to keep the pressure down

Source: Bradford White

But even with the valve, all that extra pressure can wear down the tank over the years.

You have this problem if: Your water heater T&P valve keeps opening to release water. Also, if the T&P valve goes bad/starts leaking (which it will eventually), then pressure will continue to build in the tank, leading to a burst or explosion.

How to prevent: Pressure builds in the tank when you set the temperature too high (140-145 degrees).

Make sure your water heater’s temperature is around 120-125 degrees. Any higher than that and not only will you increase the pressure in the tank, but you also increase the chances of getting scalded.

Also, test the T&P valve at least twice a year to make sure it can relieve your tank of pressure.

You can find the valve on the top or side of the tank. Just turn the switch up for 5 seconds and make sure it can release water (watch your feet, that water will be hot!)

Typical locations of a T&P valve.

The best way to prevent water heater bursts

While you can easily do all these maintenance tasks yourself, they’re easy to forget.

So, the best way to keep your water heater from bursting is to hire a plumber to maintain your water heater once a year. So, you get the peace of mind you want without having to do the maintenance yourself.

If your water heater has not had professional maintenance in the past year or more, we can help.

Posted in: Tips

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