Boiler Not Working? Find Out Why and How to Fix It

If your boiler has suddenly stopped working, the first thing to do is take a deep breath and don’t panic. A modern boiler is a complex piece of equipment, and many things could have gone wrong with it, but the good news is that some of them are some simple, free fixes, which we aim to explain in this article. 

There will also be specific problems that require the expertise of a Gas Safe Engineer, so if our simple problem-solving techniques do not solve the problem, then get in touch with the professionals as quickly as possible. Let’s look at some of the most common issues you might be facing and how to quickly and easily resolve them. 

Have You Paid The Gas Bill?

Are you on a pay-as-you-go gas meter? Has your gas credit run out? Although this can be frustrating and involve a trip to the local newsagent to top up your meter, this problem is quickly resolved and is nothing more than a minor inconvenience.

Boiler Pressure Guage

If you have a traditional direct debit arrangement with your gas supplier, check to see if your direct debit went through just in case something has gone wrong. An easy way to check if your gas supply is working, provided you have a gas hob or cooker, is to turn on the hob. If the gas lights and remains on, then you have eliminated the gas supply as the problem. 

Has Your Boiler Been Accidently Turned Off? 

Another all too common problem is that the boiler has been accidentally turned off. Many boilers are located in airing cupboards, which like the cupboard under the stairs, become a dumping ground for towels, bedding, and any other excess clothes. If too much is forced into the cupboard, the boiler switch can inadvertently be pushed, turning the boiler off. Before calling anyone and risking an excessive call-out fee, check that your boiler is switched on. 

Has The Boiler Pilot Light Gone Out? 

Your boiler has a little pilot light, which is like a miniature version of the Olympic Flame. This light burns constantly and is the beating heart of your boiler jumping into action when you need hot water or for the heating to come on. Although it is rare, a draft or sudden breeze can result in the pilot light going out.

On many boilers, there is a small hole in the front to enable you to visually see whether or not the pilot light is on, on the more modern devices, the solution may be as simple as turning off the boiler and restarting it. If the pilot light comes back on, this may be the end of your problems, and at a grand cost of zero pounds and zero pence. 

Is Your Boiler Low on Pressure? 

Boilers push hot water around your heating system using pressure. If the pressure drops below a certain level, then the system will stop working because of low boiler pressure.

Depending on the brand the following fault codes may be displayed:

Ideal Boilers F1 Fault Code

F22 Error on a Vaillant Boiler

F75 Fault code on a Vaillant Boiler

E119 code on a Baxi Potterton Boiler

There are a couple of reasons why the pressure will drop. Over time the pressure will decrease due to the natural process of the boiler working. You can simply turn a tap generally located under the boiler to fix this, which adds more water to the system. You will be up and running again in a matter of seconds.

However, if you experience a dramatic drop in pressure within 24 hours, you may have a leak in your system. Some leaks may be evident, with puddles of water appearing close to the source of the leak. However, not all leaks are created equally, and although it does not take much to reduce the pressure in the system, a minuscule leak can be the source of the problem but is very difficult to locate. ADI is the leading and original leak detection company within the United Kingdom.

We have the tools, knowledge, and expertise to find any leak you might have quickly and efficiently. Once the leak has been located, we or your local plumbing engineer can quickly and efficiently rectify the problem, and you will have a warm and comfortable home once again. 

Quick Read: What Is A PRV? (Pressure Relief Valve)

Is It Winter? – If So, Check your Condensate Pipe 

Depending on the time of year, when a boiler is working correctly, it will inevitably cause condensation. Manufacturers of boilers developed a condensate pipe system, which takes the condensation generated by your boiler, and deposits it outside your property. Because there is only a tiny amount of water involved and due to the fact that it will be dripping slowly, there is a high risk that this water will freeze in winter conditions.

Once the water has frozen, this forms a blockage for any further condensation, which in turn will cause the boiler to stop working. Find your condensate pipe, which is typically attached to the nearest outside wall to your boiler. Get some warm water and slowly pour it over the frozen pipe until you see the frozen water melting.

Once this has been achieved, reboot your boiler, and you should be good to go. If this becomes a regular occurrence, try wrapping the external pipe in foam or some other type of insulating material to prevent it from happening in the future. 

Check Your Thermostat

In most modern homes, the thermostat is not located in a different location to the boiler. Although this is very convenient, it can be the source of a heating system failure.

The thermostat generally runs on batteries; check to see that there is still power being supplied; it could be something as simple as the batteries running out. Check what term-erasure the thermostat is set at; someone in your household may have inadvertently turned it down too low, which is why the heating isn’t coming on. If your thermostat works over WiFi, check the connection in case that has dropped.

Finally, check the timer settings on the thermostat. If the clocks have gone back or forward, this could be the simple explanation why your heating is not working. In all of these instances, the only cost to resolve the problem could be a new set of batteries for the thermostat. 

Boiler Refuses to Turn On 

Sometimes no matter what, your boiler will simply not turn on. This is more likely to be some type of electrical fault; in most cases, it may well be a broken or faulty circuit board.

If all of your other electrical appliances are working correctly, then this indicates that the problem lies with your boiler. At this point, you have no alternative but to call out a Gas Safe Engineer. Unfortunately, circuit boards are not an inexpensive fix, and it might be a good idea to consider replacing the entire boiler. 

Heating Working Fine But No Hot Water 

A Combination boiler does two key jobs, it powers your central heating and heats your water. A diverter valve is a little like a traffic policeman. It diverts the heat to where it is needed. If you are not at home, and the thermostat is set to warm up your home before you get in from work, then all of the heat is directed towards your radiators.

However, once you get in from work and run a warm bath, the heat is temporarily diverted to the water system, or in some cases, to both systems. If your heating system is working but there is hot water, the diverter valve could be stuck. This will require the knowledge and expertise of a Gas Safe engineer. 

Heating Appears To Be Working, But The Radiators are Not As Warm As They Used To Be 

Depending on your viewpoint, this may not be a total disaster. As your heating system works, it generates congealed water from minuscule parts of metallic debris, commonly known as sludge.

As you can imagine, this sludge tends to be heavier than normal water, meaning it sinks to the bottom of radiators and can also cause blockages.

Although your boiler is working hard to generate heat, the sludge essentially prevents that water from circulating around the system, which is why your radiators are not as warm as they once were. The solution is for your system to be flushed by a heating engineer. 

Hopefully, this guide has helped explain the various issues that could be causing your boiler not to work, and we hope that some of the free options above were sufficient to resolve the problems and get you back in business.

If you feel that you may have a leak somewhere in your heating system then contact our friendly customer service team here at ADI Leak Detection on 0800 731 3843 and see how we can help you.