Why Water Heaters Burst?

water heater burst

When water heater leak or overflows, extensive damage to your home can be expected. But, when a water heater bursts, then the damage and the danger heightens immensely. Aside from the hot water being absorbed by the floors, walls, and boards that can lead to swelling and eventually rot and decay, a bursting water heater can cause serious burns if it touches your skin. What are the reasons that can lead to an exploding water heater?

Common Reasons

Luckily, there are only a few common reasons why water heaters may burst unintentionally. Here are what you should be aware of.

Buildup of sediment – this is the number one possible cause of a water heater explosion. The minerals from hard water will result in the accumulation of sediment over time. These will eventually settle at the bottom of the storage tank where it will create and insulating layer. This will force the water heater’s burner to run longer than usual resulting in the deterioration of the tank aside from possible overheating.

An indication of this problem is a bubbling, popping, or knocking noise coming from the storage tank of the water heater. The noise is the result of the boiling water that is trapped underneath the sediment layer.

The only way to prevent the buildup of sediment inside the storage tank is to make sure that you regularly flush and drain the water heater at least once a year.

Rust and corrosion in the tank – Steel, which is mostly iron, is the usual material used for the manufacture of water heater storage tanks. This means that there is a high probability that after a few years of operation, the storage tank will eventually succumb to corrosion and rust.

This is despite the presence of an anode rod that is designed as an internal rust protection system for the water heater. The anode rod is about 3 to 5 feet long and rests inside the tank to attract rust. This is why it is often referred to as a sacrificial anode, which must be replaced regularly. If the hot water coming out of your faucet or shower is brownish in color, then you may have rust in your storage tank.

You can prevent this from happening by inspecting the sacrificial rod at least once every 2 years and change in in about 4 to 5 years of operation. If you are using a water softener, you may need to change the sacrificial rod earlier.

Excessive internal pressure – it is inevitable that pressure will build up inside the storage tank. This is normal because water will expand as it is heated and will exert pressure on the walls of the storage tank. The dangerous thing is when this internal pressure becomes too high and allowed to continue to rise.

With water heaters, this is usually prevented by the temperature and pressure relief valve. The valve opens up to ease the pressure. The valve however will eventually wear down due to age. You will know that you have an internal pressure problem when the temperature and pressure relief valve keeps on opening or leaking.

One way to prevent this from happening is to make sure that the thermostat is set to 120 up to 125 degrees only. Anything higher than this will not only increase the internal pressure dangerously, but also puts you in danger of scalding. Inspect the temperature and pressure relief valve at least twice a year to make sure that it is in working condition.

The threat of water damage is further heightened when you consider that when a water heater bursts, it does not shut off automatically. This means that the heating element will continue to burn. And without anyone there to shut it off, you are facing a worst case scenario of exposed flames left unattended.

Call a licensed plumbing professional to give you water heater a thorough checkup to avoid a burst water heater condition.


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