Can A Boiler Explode? Signs of a Overheating Boiler

Not many people would be able to live without their boilers. While these units are expensive to install, they’re essential in the home. Their primary function is to heat the water and home using steam.

During the process, pipes and radiators transport the steam and heat. The great thing about boilers is that even though they come at a price, you get a long life span from them, and they’re pretty energy-efficient.

If the boiler in your home isn’t well maintained, you may have the bad experience of it exploding. This explosion is most often due to pressure buildup or, in some instances, mechanical failure.

Some of the most common signs that your geyser is about to explode are a terrible smell (usually reminiscent of rotten eggs), discoloured water (typically brown), or a strange pinging sound emanating from the pipes.

Boilers tend to explode more often than you might think, so it’s essential to be aware of the telltale signs that your unit will explode soon!

First things first, let’s cover the basics.

What Is A Boiler?

A boiler forms an integral part of a home’s heating system. Its primary function is to convert water, heated with either gas or electricity, into steam, and then the steam warms the house by being distributed through pipes and radiators.

The boiler is typically centrally located to spread the heat consistently through the house.

What Happens When A Boiler Explodes?

When a boiler explodes, it is referred to as a “catastrophic failure.” There are three common causes of a boiler explosion:

  1. The pressure has increased too high.
  2. The system has overheated.
  3. The outer shell or other components of the boiler are weak.

Telltale Signs Your Boiler Is Going to Explode

A boiler won’t spontaneously explode without an underlying reason. And luckily, your boiler will present you with a few red flags before it does explode. Below are a few things to look out for:

  • There’s sulphur or rotten egg smell in the vicinity of your boiler. This smell means that your boiler has a gas leak, which can certainly cause an explosion.
  • Your water has a strange colour. If your water is brown or reddish, it is a sign of sediment building up or rust in your pipes. Any sort of buildup can reduce the flow of your water, which increases the pressure in the system and can lead to an almighty explosion.
  • There’s a strange sound coming from your pipes. If you hear a pinging, banging, or popping noise, it is also a sign of sediment and rust in your pipes.
  • Your water has a bad odour (rotten eggs too). This usually means that your water is contaminated with microbes.

How To Save Your Boiler From A Possible Explosion

The first thing to note is that boiler explosions are dangerous, so make sure that there are no family members near the boiler’s vicinity. Here’s what to do next in different scenarios:

  • There is a smell of rotten eggs around the boiler: turn the boiler and gas off and then call a professional to tend to the problem.
  • The water smells like rotten eggs: immediately replace the anode rod.
  • The water is discoloured, or there’s a strange sound coming from the pipes: turn off the system and clean the pipes and the boiler. Make sure to clean the heat exchanger too.

Let’s Boil Down The Causes of Boiler Explosions

Realistically speaking, a boiler is a prime suspect for an explosion. After all, when you add water, heat and high pressure in a confined space, excess energy is bound to build up. So let’s take a closer look at each of the causes of boiler explosions.

There’s a Buildup Of Excess Pressure

A buildup of pressure is the number cause for a boiler to explode. When energy builds up (pressure), it needs to get released, and if it doesn’t find a way out, it will cause an explosion. Modern boilers are designed with this in mind and can typically handle more pressure than older or more outdated boilers.

The Boiler Has Sprung A Gas Leak

The most dangerous part of a gas leak explosion is that there’s usually fire. While gas leaks can have several causes, you will most commonly find a faulty connection or that the container holding the gas is defective or damaged.

The Heating System Malfunctions

The pressure relief valve may stop working, or the boilerplate may be sporting some corrosion – this is enough for a system malfunction. When the system malfunctions, the water level drops, and an explosion is almost guaranteed.

It typically means that regular maintenance and safety checks haven’t been met for a system to malfunction. Most boilers have up to three valves to help prevent explosion and act as a backup if the main valve stops working.

Buckling Crown Sheet

The crown sheet itself doesn’t boil because there is pressure within the boiler; the crown sheet itself doesn’t boil.

For it not to boil, there should be water covering it, but if the water level drops, the crown sheet will buckle, and pressure will build up. In most instances, this results in an explosion.

How To Keep Your Boiler In A Tip-Top Non-Explosive State

While boilers aren’t exploding in every home every day, you need to do what you can to prevent such an unpleasant and dangerous occurrence. This means that you need to take preventative and maintenance measures to keep your boiler in its best possible state. Below are a few pointers on how to do that:

  • Carry out regular maintenance checks on your boiler. If something isn’t 100%, hire a professional to assist.
  • Check the maximum pressure level of the boiler and set the unit’s pressure level below that. This means that the boiler is never operating at full capacity.
  • Set the boiler’s pressure relief valve lower than the maximum pressure capacity of the unit.
  • Update your boiler regularly. Don’t let it go too out of date. This requires checking and replacing rods, valves and so on.
  • Turn the boiler off when not in use and at night. While this won’t earn you efficiency points, it will provide you with peace of mind.

Can a Boiler Explode? Final Thoughts

Unfortunately, boilers can explode if an issue is overlooked or not noticed in time. To avoid unnecessary trauma and damage, regularly check your boiler and only ever contract repairs and maintenance to a qualified professional.

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