Can a boiler explode from overheating or high pressure & how to prevent it?
Yes, a boiler can explode, but they rarely do as most modern boilers are built to withstand reasonably high pressure, therefore if this gets too much then an explosion could happen.
Whilst this is more common in older boilers, which aren’t that many now, most new boilers have fail-safes like a pressure relief valve or will just stop working if the pressure gets too high. This is called boiler failure.
Old boiler over 10 years old costing you more in gas bills and repairs? Get a fixed price online for a new boiler installation from Easy Boilers now.
What can cause a boiler explosion?
If you are seriously worried about a potential boiler explosion, then either turn it off or call a Gas Safe registered engineer right away due to the fact high boiler pressure, overheating, or loud noises are all signs that something isn’t right that can lead to your boiler going bang.
This is usually caused by a faulty boiler or a bad installation, and potentially your pressure relief valve may be blocked or too tight, or a wiring error which is stopping the boiler from realising pressure is building.
What are the signs that your boiler is going to explode?
Here are some tell-tale signs that a boiler is on the verge of exploding.
For example, the following different problems are all potential issues that could lead to a boiler explosion or catastrophic failure.
All of the following symptoms can lead to an exploding boiler in a worst-case scenario but they can also be other issues too, which, if you catch nice and early, can save you a hefty bill or any damage to your home.
If you think your boiler could explode, we strongly suggest that you get a new one.
Too much pressure in your boiler
A combi boiler’s normal running internal pressure is around 1.5 bar or 21psi.
If there is too much pressure in your boiler, you can release it by bleeding your radiators, but your central heating system must be cold, so you don’t get burnt.
If you try to do this when hot and under high steam pressure, you could cause serious injury to yourself.
The type of boiler you have will change how risky overheating on the boiler is.
Modern boilers are much safer, so if you have an old boiler, it may be time to upgrade.
Overheating or excessive heat when you go near your boiler
You should be able to touch your boiler at any point.
If your boiler is extremely hot or you can’t touch your boiler, then it needs to stop and shut down right away.
Internal pressure builds up, and your boiler is not working properly.
Your boiler smells like rotten eggs.
If your boiler is leaking or central heating water smells funny, this is a tell-tale sign that something is wrong and parts could be compromised, causing a build-up of sludge or sediment.
This then builds pressure and could cause boiler explosions.
Excessive noise coming from the boiler
If your boiler is making really loud noises, this could be high pressure in your boiler building up or broken safety valves, which can make your boiler explode. Boiler kettling is another common issue too.
The operating pressure of your boiler keeps rising
All combi boilers have an operating pressure gauge. If your boiler pressure gauge rises above 3 bar continuously, you have excessive pressure, which needs to be released.
This is the job of pressure relief valves, but if this is not working properly, you may need to bleed your radiators. Low boiler pressure is less of an issue.
The broken pressure relief valve
Boiler failures can often be caused by a broken or stuck safety valve.
Is your boiler overheating?
If your boiler is overheating, you should immediately call a heating engineer.
A boiler that is getting too hot is an emergency and needs to be fixed immediately, as this could cause the explosion you are worried about.
Letting your boiler cool down is the most important thing to do in this situation.
What to do if your boiler is getting too hot?
If you think it is safe to do so, you should turn off your boiler at the mains, and if you know how to, if possible, stop the water supply.
This will, in turn, stop any build-up of pressure and prevent your boiler from exploding. If you have managed to do this, you must let your boiler cool.
Let the boiler cool down gradually.
Do not switch your boiler back on until a Gas Safe registered heating engineer has taken a look at your boiler, as there may still be excess pressure.
You will likely need a new boiler.
Find out how much a new boiler cost now by getting a quote online.
Back boiler explosion – What to look out for
Back boilers are different from combi boilers as you can’t see or hear everything going on, and a new modern boiler is in a cupboard.
Back boilers are generally older, too, so they are much more susceptible to things going wrong.
A back boiler explosion could be disastrous but ensure that if it is making loud noises or giving out excessive heat, you get someone to look at your back boiler fire right away.
What to do if your boiler explodes?
If your boiler explodes, this is an emergency, and you will need to call the gas emergency helpline on 0800 111 999.
You must call 999 and ask for the fire service if it is dangerous or on fire.
Boiler explosions are serious and need fixing right away.
There is also the risk of carbon monoxide poisoning or fuel explosion.
If you believe there is no immediate threat and the boiler is safe, you can call a gas Safe registered emergency heating engineer to come out as soon as possible.
They will condemn the boiler and shut off the gas.
You will then need to make arrangements for a replacement boiler installation.
What to do to prevent boiler explosions
Whilst boiler explosions are not that common anymore; we strongly recommend that you do the following things to make sure.
Whilst a modern gas boiler can withstand excessive pressure, all the following checks and proper maintenance tips are great for keeping your gas boiler in tip-top condition for as long as possible.
- Ensure that you get an annual service of your boiler every year. This typically costs around £90 and can make sure that your boiler is at the right pressure and working correctly. This is much cheaper than paying for repairs or mechanical failure after a boiler explosion.
- Physically check the boiler pressure yourself periodically. There is an easy-to-read pressure gauge on most combi boilers in the UK. This should be around 1.5 bar. Some of the best combi boilers can check and amend the pressure themselves.
- If you are replacing a boiler, you must ensure that you use a Gas Safe registered installer. This lessens the chance of a bad installation which is one of the more likely reasons for boiler explosions.
Replacing an old boiler can prevent boiler explosions
If you have an old combi boiler, it may be time to get a new one if you think your old one is dangerous.
As we say, such explosions are rare, and most boilers can protect themselves.
You can ensure that you get a top-of-the-range boiler with 1st class boiler replacement by getting a boiler quote online now with Easy Boilers.
If your boiler is completely broken, you can even get an emergency boiler installation and get a new boiler fitted fast in under 24 hours.
