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Boiler Not Working? Common Boiler Problems & How To Fix

Boiler not working? Common boiler issues you can fix

boiler not working

Is your boiler not working? The following are the most common boiler issues and simple fixes for these problems that anyone can do at home and ones that require a Gas Safe registered heating engineer.

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No matter whether your boiler is not turning on or it is making weird sounds, it can be very concerning, especially during the colder months of the year when you rely on your boiler for a comfortable home and warm showers.

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Nothing is more frustrating that a noisy central heating system that has stopped working, or as we call them, boiler breakdowns. If your boiler has completely broken, then in this guide, we will explain everything that you need to know about common boiler issues and the steps that you should take. 

Be sure not to attempt to do anything with your boiler on the inside or mess with the gas, as this could cause some serious injury.

Only a Gas Safe registered heating engineer can do this.

If your boiler is getting older or out of warranty, why not consider a boiler cover which can save you from large repair bills all from a small monthly payment?

What you need to check first is if your boiler is not working

Is your boiler switched on

broken boiler no hot water

This may sound like a patronising statement at first but we promise that we’re not trying to make you mad!

There have been a lot of boiler companies that have gone on call-outs only to discover that the boiler is not turned on; sometimes at the mains. This can be human error.

Someone may have turned the boiler off or the gas supply by mistake. However, this usually occurs because of a power cut and can affect gas appliances in your home.

You may have even had a power cut during the night and not realised it because you were asleep. So, before you spend your time and energy on calling a company to come and fix your best combi boiler, make sure that it is turned on in the first place. 

It is always a good idea to check the fuse box at this stage.

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Try resetting the boiler

Your boiler could just need resetting after a power cut or being switched off. this can often solve a problem and cause a boiler to start working again with no issues.

If you reset your boiler and it doesn’t work, ensure that you look out for fault codes or error codes as this may tell you exactly what is wrong with the boiler.

Price up a new boiler now if your boiler is over 10 years old as they become less efficient over time. We only recommend the best boiler installers to complete any installations

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Check your gas bill to make your boiler work

boiler not working

It is also important to make sure that your gas bill is paid. Or, if you are on a meter, make sure you have credit. You may have recently switched bank accounts and forgotten to change your direct debit, for example.

If your energy bill has not been paid for any reason, even if it was a simple oversight, your boiler is not going to work. It could be that there was simply a mistake on the company’s behalf.

They may have switched your gas off by accident. Give them a call and make sure everything is as it should be and you may have heat and hot water back on quickly.

There are a number of different problems that people can have with their boilers. Let’s take a look at some of them…

If you think it may be time for a new boiler, why not check out some of the latest boilers such as the Worcester 4000 or the superb value Viessmann Vitodens 050-w

Check the water pressure to fix a broken boiler

boiler not working no hot water

Now that you are sure that you have paid your bill and your boiler is indeed turned on, you need to make sure that it has water pressure. Over time, boilers will start to lose water pressure naturally.

There are a number of different reasons why you can get low boiler pressure and you do not need to be a Gas Safe registered engineer to view and fix this fault code. You should look at the pressure gauge on the boiler. You will see a feature that looks like a clock.

Whenever the boiler is turned off, the arrow should be pointing toward the green zone, around 1 bar. There is also such a thing as the boiler pressure being too high. 

If the boiler pressure is too low, you should be able to resolve this at home within a few seconds. The first thing that you need to do is locate the filling loop.

If you look underneath your gas boiler, there should be some pipework. Here, you will find the filling loop. It is a silver Flexi pipe that has either one or two taps on, which tend to be black.

In order to increase the pressure, you are going to need to open the taps, full, until 45 degrees of pressure is reached. It will lock at this point.

You will see the pressure rise on the boiler’s pressure gauge to around one bar while you are going through this. Close the taps once you are in the green, and there you have it; your boiler has been repressurised. 

Has the pilot light gone out on your boiler

boiler not working

The boiler pilot light, which is essentially a tiny internal flame, will need to be alight in order to ignite the gas and deliver hot water and heat.

If it is not, it is not going to burn the gas when the boiler is active. There are occasions whereby the flame will go out. This could happen because of a sudden draft, for example.

If you have an old boiler, simply peer through the casing and you should be able to see whether there is a flame or not. Try resetting or restarting your boiler if this is the case.

If the boiler still does not work, you are going to need to get a heating professional engineer to sort out the issue or even the person who did the boiler installation.

If it is an old boiler, we strongly recommend you consider how much a new boiler costs as it may be the cheaper alternative over time.

Check the boiler for a frozen condensate pipe

A frozen condensate pipe is something you should check during the winter. The condensate pipe travels from your boiler to the nearest outside wall in most cases.

This is where excess liquid, which is caused by condensation from the boiler, is deposited. In cold weather, this little quantity of slow, dripping water can be vulnerable to freezing.

A blockage will occur if there is a frozen condensate pipe. This means that there is no escape route for the water, causing your boiler to shut down because of this. This is one of the more common reasons for boiler failure but luckily is one of the easiest fixes.

In order to fix a broken boiler that is not working, you should gently pour warm water over the condensate pipe that has become frozen until the frozen water melts away.

Once you have done this, you should reboot your boiler. It is a good idea to check on your pipes regularly in order to try and prevent this from happening. 

Check the thermostat on your boiler

boiler not working

If you still have not gotten to the bottom of your boiler issues, the next step is to check the room thermostat as it may be that your heating is at the ideal room temperature set. Boilers tend to be held accountable for the shortcomings of their controllers.

So, it is a good idea to make sure that your boiler has not failed because of a problem with the thermostat. The first thing you should do is make sure that the boiler is switched on and that it has working batteries, which are fully charged.

Make sure that the temperature is turned up to the level that is needed. After this, if applicable, you should check the Wi-Fi connection in regard to your boiler thermostat. Take a look at the time settings as well. Make sure there are no unnoticed daily schedules, stand-by options, or vacation modes that have been set.

In order to fix your thermostat, firstly, replace the batteries. After this, you should clear any settings and then restore them to manual operation. If all else does not work, then you need to refer to the thermostat manual. 

When you will definitely need a professional…

There are a number of different circumstances that are going to require a professional Gas Safe registered engineer. So, let’s take a look at these in further detail…

Boiler pressure problems that have been caused because of broken parts

Pressure is a necessity for boilers, with a balance being needed. If boiler pressure is lost, this is going to mean that there is not enough water running through the boiler.

This means that your boiler is not going to be able to supply your home with the hot water that you need.

On the flip side, if there is too much pressure, your boiler is not going to have enough time to ensure that the water is heated properly.

There can be a lot of other issues as well, for example, internal parts being put under pressure, resulting in leaks. 

There are a number of different culpable boiler parts. This includes the heat exchanger, pressure release valve, and expansion vessel.

Such problems can result in expensive repairs and often, you will be better off going for a new boiler.

Of course, this depends on the age and state of your existing boiler. 

A boiler leak in your heating system or boiler

Leaks within the heating system, i.e. the pipework, or the boiler’s internal parts are not only bad for your floorboards and carpets.

They are also bad because they can cause damage to your boiler that cannot be reversed. In order to check for these sorts of issues, you should look for drips and patches of water underneath the boiler. You should also look at the pipes throughout your home, especially around the bends and joints.

If you do notice a leak, you are going to have to get in touch with an experienced gas boiler engineer who can check over your central heating system, ensuring that any faulty parts are replaced or that any leaks in the pipework are secured. 

Your boiler is working but you have got no hot water

This is another issue that a lot of people experience. The boiler is turned on yet there is not any hot water. When this happens, it indicates that there is a problem with one of the parts in your boiler. In all likelihood, it is going to be the diverter valve that is to blame for this issue.

As you may be able to tell from the name, this is the part that is responsible for diverting water to your hot water outlets, radiators, or both, depending on where you’re demanding water.

So, when this happens, the obvious solution is to get the diverter valve replaced.

There may be cases, though, whereby you need to invest in a new boiler, so it is worth keeping this in mind. 

If you have noticed that your radiators are not getting hot yet your boiler is working, the issue here probably does not lie with your boiler at all.

As time passes, heating systems, i.e. radiators and pipes, will end up being congested with dirty, congealed water and metallic debris. This causes system blockages.

If your radiators are cold at the bottom, this is a clear indicator that you have got an issue with sludge which can you to have hot water working but radiators and central heating does not work at the same time.

Your boiler simply will not turn on

If your boiler will not turn on, i.e. there is no power to your boiler whatsoever, then it is probably an electrical issue. You will know that this is the case if your boiler has no sign of life.

This is usually a busted circuit board, otherwise known as PCB. You could end up spending a few hundred pounds to replace this, if not more. However, it can often be sensible to simply get a new boiler quote.

This is especially the case if your current boiler is an old model and is not energy efficient. In order to determine whether this is a problem, your only real play here would be to turn the boiler off and on again at the mains.

You will need to get in touch with an experienced engineer in order to get to the bottom of the problem. If it is your PCB board that has broken, then a replacement is going to be the only solution, and this is not cheap.

A dripping or leaking boiler

One of the most common causes of a boiler not working is a leaking combi boiler. A leak can occur anywhere in the system and significantly reduce boiler pressure; if it occurs after the boiler pressure gauge, the readings may not even detect it.

Examine your system for signs of leaks.

Examine everything that is exposed, including radiators and the boiler itself. If you don’t see any obvious signs, you may need to contact an engineer to inspect the entire central heating system and boiler.

Is the boiler’s pressure constantly dropping?

If the pressure in your boiler continues to drop after topping it up, this could indicate that there is a leak in your existing system.

These leaks can be difficult to locate because they require following your pipework from the boiler throughout your home to every connection point.

We also have a more detailed guide on what to do if your boiler pressure is falling.

Boiler still not working?

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So there you have it: some of the most common issues that are associated with boilers today. If you have noticed any of the problems that have been discussed in this guide, it is always advisable to get an experienced engineer in to resolve the problem because the last thing you want to do is run the risk of it getting worse. 

When looking for an engineer, make sure that they have plenty of experience in the make and model of boiler that you have.

For instance, some engineers only specialise in certain boilers, be it Baxi Vaillant or Worcester, for instance. Aside from this, make sure that they have all the necessary qualifications and experience.

Do not simply assume that this is the case. You should also take your time to do some research online. Read what other people have had to say to make sure that the company in question has a good reputation.

The last thing you want to do is end up using the services of a business that has let many people down in the past. If you are wanting a new boiler you can compare boiler quotes on our homepage.

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