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Water Heater Burst: Why This Happens And What To Do Next

Water Heater Burst

When a water heater bursts in a home, it is a shocking event, not to mention a messy one, and it could potentially cause a lot of expensive damage. If your hot water heater burst, you’re probably wondering why this happens and what to do next.

In general, the basic reason why hot water heaters burst is that there is corrosion within the tank, which can lead to the tank bursting at its seams. Unfortunately, there are several possible underlying causes that can contribute to water heater explosions, and it’s not always apparent which one is the culprit.

Sometimes there are risk factors or warning signs that could indicate a water heater explosion is imminent, but not always. In order to understand the risk factors that could contribute to a water heater exploding, it’s important first to understand the type of water heater that you have in your home.

Types Of Water Heaters

There are two main types of water heaters: conventional storage water heaters, which are the most common and popular type of water heater that most people install in their homes; and tankless water heaters, which are also popular, and which can be a good choice based on various criteria within a particular home.

Conventional Water Heaters

Storage (or conventional) water heaters have a tank that holds a set amount of hot water, which is heated with either electricity, gas or oil, depending on the particular home and system. When you turn on a faucet in a house equipped with a storage water heater, the water heater releases hot water from the top of the tank and sends it through the pipes to your sink, shower or bath. The tank is then replenished with cold water, so the tank always stays full.

Tankless Water Heaters

True to their name, tankless water heaters don’t operate with a tank of water that is constantly being heated and replenished; rather, they operate by heating water directly, on demand, each time a hot water faucet is turned on in the home. Cold water travels through either an electric or gas heating element within the tankless water heater on its way to the tap and comes out hot and ready for use.

Since tankless water heaters do not store hot water, they can’t explode in the same way that storage water heaters can. There have been cases of tankless water heaters exploding and catching fire when they were installed with defective pressure switches. Generally speaking, however, the main type of water heater that can burst is a storage water heater, so if the water heater in your home has exploded, it’s likely to be a conventional water heater.

water heater explosion warning signs

Water Heater Explosion Warning Signs

Since storage water heaters are made of metal and store large volumes of heated water, they carry an increased risk of leaking or even exploding as they begin to rust at the fittings and seams over time. If the thermostat controlling the water temperature within the tank is faulty, or if mineral buildup inside the water heater prevents the thermostat from sensing the water’s temperature correctly, the water could become overheated. This will expand its volume within the tank, causing it to press at the tank’s fittings and seams. If these fittings and seams are rusted or corroded, the pressure could result in a leak or even an explosion.

Here are some risk factors and warning signs of an increased risk of water heater leak or explosion:

  • Your water heater is more than 10 years old.
  • Your water heater makes clanking, banging or rumbling noises as it heats up, indicating that sediment has built up and hardened inside the tank.
  • There is visible rust on the outside of the water heater, especially located at the pipe fittings or the seams that run down the tank.
  • There is rusty water coming from your water heater, indicating that there may be rust building up inside.
  • Your water heater is leaking, which could indicate either a crack somewhere in the tank or a malfunctioning temperature-and-pressure (T&P) relief valve.

It’s important to note that water heater leaks aren’t always serious, and don’t always mean the tank might explode, or even that it needs to be replaced. If there is a leak in the water supply lines, for example, which lead into the top of the heater, this is a problem that is relatively easily fixed, and which is unlikely to contribute to a water heater bursting.

Another, similarly uncomplicated and fixable source of water heater leaks is a leak at the water heater nipples; these are located at the top of the water heater, where they connect the water pipes to the heater itself. If the T&P valve is leaking, it may need replacing or may indicate a larger problem. If the water tank itself is leaking, however, it isn’t fixable, and the whole tank will need to be replaced.

what to do when water heater leaks

What To Do When Water Heater Leaks

If you find water dripping or seeping out of your water heater, or pooling around it, it means your water heater is leaking. If you find a leak, it may be best to call a plumbing professional to diagnose the problem and determine how best to handle it. If you choose to tackle it on your own, there are a few things you can do.

Turn Off The Cold Water Supply

Shut off the cold water going to the tank by closing the valve located on the cold water pipe that feeds into the top of the tank. To close off this or any other water shutoff valve in your home, turn it clockwise, just as you would turn off the water at a regular faucet. If your water heater has a lever-type cold-water shutoff valve, turn it 90 degrees from its open position to close it off. If there is no water shutoff valve available, you’ll have to turn off the main water supply to your home.

Turn Off The Power   

Next, shut off the power to the hot water tank at your home’s electrical breaker box. If you don’t shut off the power, the heating elements within the tank could continue to stay hot, which could pose a fire risk.

If you have a gas-powered water heater, you’ll also need to shut off the gas line leading into the tank.

Find The Leak

Now it’s time to determine where the leak is coming from. Likely locations are the T&P valve, the drain valve or one of the pipes or fittings that feed into the top of the tank. If you see any rust or corrosion on the outside of your water heater’s tank, pipes or fittings, these could also be the source of the leak.

Repair The Leak

Once you determine the source of your water heater leak, you’ll have a better idea of what steps you need to take to fix the problem. It may be a simple fix—such as using a wrench to tighten fittings or replacing the T&P valve—but it may be something more complicated. You may even need to drain the tank, remove the water heater and install a new one.

what causes a hot water heater to leak

What Causes A Hot Water Heater To Leak

When determining what causes a hot water heater to leak, you’ll need to choose from several possibilities. You may have an older tank that has loose fittings, a loose drain valve, a faulty T&P valve, a cracked storage tank due to rust or too much pressure inside the tank due to sediment buildup or a malfunctioning temperature gauge.

Your hot water heater may also leak simply due to age and wear-and-tear over time, especially if you don’t have a regular maintenance routine set up to service your water heater. Because there are so many possible causes of water heater leaks, routine water heater maintenance is very important as a safety measure to guard against the possibility of an explosion.

hot water heater busted water everywhere

Hot Water Heater Busted: Water Everywhere; What Now?

If your hot water heater has burst and there’s water everywhere, you have a problem on your hands that needs immediate attention so it doesn’t get any worse or cause any further damage to your home. These water heater emergencies often require professional intervention, but here are some immediate steps to take if you find that your hot water heater has burst:

  • First, turn off the power and cold water supply to the tank as described above, and if you have a gas-powered water heater, you must also shut off the gas line to the tank.
  • When you are ready to start cleaning up the water that leaked out of the water heater when it burst, be sure to take photographsfirst of the entire leak, including any damage to your home itself or to furniture, boxes or other items. This will help your homeowner’s insurance or home warranty companies to determine the extent of the damage and the cost to replace or repair your items.
  • Use a wet-vac to clean up as much water as possible, and then use a dehumidifier to dry out any areas that might be prone to mold if they stay damp.

As we’ve already mentioned, most homeowners will now call a plumbing professional to avoid any common plumbing mistakes that might cause further damage. A plumbing professional can help you with common plumbing problems and advise you on what to do next. If your water heater exploded, it can’t be repaired and will need to be replaced. 

Keep in mind that there are certain steps homeowners can take to keep their hot water heaters in good shape and minimize the risk of a water heater explosion. In general, setting up a regular maintenance schedule with a licensed plumbing professional is the best way to ensure that your water heater stays in excellent working order. Homeowners can also release their water heater’s T&P relief valves every six months, and have a plumbing professional inspect those valves annually and replace them at appropriate intervals over the lifetime of the water heater.

ABC Can Handle Your Water Heater Problems

A burst water heater requires immediate attention and can involve significant water and associated property damage. These types of plumbing and appliance problems are often best left to the pros. The licensed plumbers at ABC Home & Commercial Services can help you decide on the best replacement water heater for your home, and will install it properly and set up a maintenance schedule to keep it working at optimum efficiency. Your ABC technician can also help if your water heater is in need of repair. We service and install both storage and tankless water heaters, so our customers can feel safe that their home and belongings are in good hands.

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