It could be something super simple, or it could be something super expensive. Either way, you'll get to the bottom of the issue with this super guide.
If you’ve got no power to your boiler, you’ve probably lost access to heating and hot water and are likely to be absolutely gutted.
But never fear, Heatable's here to help guide you on how to get your boiler up and running again.
If your boiler has lost power, the issue is likely to be an electrical one, so in this guide, we will explore some of the most common faults, so you can get it fixed and return to normality as soon as possible.
We will be exploring the checks you can do and potentially fix yourself, as well as those that require a Gas Safe Engineer.
Need to know the cost of a new boiler quick? Find out what boiler replacement you need along with costs (takes 60 seconds).
Causes of no power to a boiler
So, to begin, let's check the basic things first (which you can do by yourself):
First, has your boiler's fuse blown?
Like most appliances that operate using electricity, a boiler is fitted with a fuse to prevent damage in the event of a power surge.
A power surge can damage key components of your boiler, so the fuse functions to break the circuit if it detects a surge so that it does not reach the boiler.
This protects your boiler, but it also results in your boiler losing power until the blown fuse is replaced with a new one.
You may also be interested in our guide to DIY boiler checks you can do before you call a Gas Safe Engineer.
Electrical supply issues
This is an obvious one, but have you lost your electrical supply? Without electricity flowing to your boiler, it will lose power.
You can usually tell this quite easily by checking the other electrical appliances in your home. If it is only your boiler that lost power, it is unlikely to be an electrical supply issue.
If you have one check your electric meter? Do you have any credit remaining? If not, this is likely to be the issue.
Learn all about combi boilers in our what is a combi boiler guide.
RCD Tripped a Switch?
A residual current device (RCD) or fuse board is traditionally located under the stairs in most homes and its purpose is to prevent you from receiving a fatal electric shock.
It does this by tripping a switch on certain “circuits” within your property, different circuits are usually zoned e.g. your downstairs light may be on the same circuit.
Your boiler may be on its own circuit and therefore have its own switch. If it is in the “off” position, the switch has tripped causing no power to your boiler.
This can occur for a variety of reasons such as a leak near an electric component, a complete power outage or a power surge.
Learn about all that's involved in a boiler replacement installation.
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Checks that require a Gas Safe Engineer
If you don’t detect any issues after carrying out the above checks, you may want to contact a Gas Safe Engineer, who will be able to carry out checks on internal boiler components.
Here are some of the most common electrical issues that happen inside the boiler that may result in no power to the boiler:
Faulty PCB (Printed Circuit Board)
The printed circuit board (PCB) is essentially the computer or the control centre of your boiler.
It synchronises all the electronic components, ensuring key processes occur at the correct time and in the correct sequence.
Here’s an example of a PCB from a boiler:
If your boiler has a PCB fault, then it could possibly lose power and switch off completely, or “lockout” and display a relevant error code.
A Gas gas-safe engineer will be able to remove the boiler cover, and investigate and carry out further electrical testing on your PCB.
If your PCB is broken, then it typically makes sense to purchase a brand-new boiler, since the PCB is one of the most expensive components of a boiler.
You can read our comprehensive guide on boiler PCB faults or our list of the most common boiler problems.
Internal Boiler Fuse Broken
Like other large appliances that consume a lot of electricity, such as electric stoves, boilers will have their own internal fuse or fuses. Sometimes boilers will have multiple internal fuses.
These are usually fuse spurs – a small socket, with a red window. These internal fuses are designed to keep your boiler segregated from the main electric circuits.
If your boiler's fused spur has blown, which can happen due to age or a power surge it will result in no power to your boiler.
A Gas Safe Engineer will be able to check the fuse spur, replace it if necessary, and re-test your system to ensure nothing underlying causes the fuses to blow again.
PS You may be interested in Gas Engineer Allen Hart explaining the most common boiler problems and how you can resolve them in the video below:
LED Fault
Maybe one of the least severe boiler problems is a faulty LED, resulting in what only appears to be no power to your boiler, but in reality, it is just the LED lights that have failed.
This can make your boiler’s interface look dead, which you can easily perceive as your boiler having no power.
Admittedly, this is not very common, but it is always a possibility.
Again, a Gas Safe Engineer will be able to carry out a simple electrical test to determine if this is the cause.
Curious to know which boiler brand performed worst? Find out in our report of the worst boilers.
How to reset your boiler
Once your boiler's electrical issue has been resolved, whether DIY or by an engineer, you will need to reset your boiler.
The majority of modern boilers have a very user-friendly and simple-to-use “reset” button. Simply press it and you are done.
Here are some examples of what the boiler reset button looks like and where it is typically located:
Image source: Worcester Bosch
If you have an older model, the resetting mechanism may be different, in which case you should read your user manual to find out more.
Got an emergency? If your boiler is busted and you have no hot water, you may be interested in our emergency boiler installation guide.
PS You may find our guide on the UK's most popular home heating system combi boilers of interest and our new boiler cost guide.
Boiler Broken?
If your boiler is broken beyond repair, very old and no longer covered by the manufacturer's warranty, it probably makes more financial sense to get a brand-new boiler installed.
If you’re aiming to get the best deal on a new boiler, consider getting a quote from us, here’s why:
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Save your quote and decide later.
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