No Power to Boiler – Causes & Solutions

Last updated: November 15, 2023

Boilers can break down for a number of reasons and the solutions usually vary in complexity and price.

In situations where there is no power to a boiler, often there is an electrical issue at the source of the problem.

This guide will provide some troubleshooting tips in order to help the investigation as to why a boiler may be suffering from the loss of power, and hopefully overcome the issue to get the heating system back up and running again.

However, our troubleshooting tips also come with a warning that if you are in any doubt regarding how to undertake the steps discussed, always call out a qualified heating engineer.

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Causes of No Power to a Boiler

There are a number of common situations that can cause a boiler to either act like there is no power, or indeed does not have a current power supply.

In order to try and isolate the issue, it is recommended that a homeowner or property tenant works through the following common causes before calling out an engineer:

Has a fuse tripped or blown?

It is common that after a power cut or power surge, the safety mechanism within a fuse box kicks in and trips a fuse.

Therefore, if a boiler is found not to have power, the first place to check would be the fuse box, to see if a switch is down.

If there is a tripped fuse, follow the instructions on the box itself in order to safely turn the switches back on.

If the switch trips again immediately after turning it back on, there may be a broken fuse or another electrical fault and therefore in this scenario, it would be time to call in a professional electrician.

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You may also find our review of the best eco-friendly boilers of interest.

Has the property lost its electric supply?

This question may seem obvious but it’s worth checking to see if the whole property has lost its supply of electricity, by checking another electrical device within the property.

If the house has lost power, next it would be sensible to see if the issue is more widespread by checking in with neighbours to establish if they are in the same situation.

If the street has lost power, there may be updates posted on the website of the electricity network giving an idea of how long the power cut is likely to last.

One final check regarding electric supply is in relation to properties that have prepayment meters fitted. In these properties, it would be worth checking that the meter has credit applied as otherwise, the system will not operate.

Got a common boiler problem? Check out our quick fix guide on boiler lockout, boiler ignition faults, boiler PCB faults, faulty diverter valves and boiler timer issues.

Should the above scenarios not be the root cause of the loss of power to the boiler then the next set of troubleshooting steps would need to take place.

However, due to the complexity of the following matters, a Gas Safe Registered heating engineer would need to be called out in order to safely investigate further.

The next steps that a qualified heating engineer would check out are:

A fault within the boiler’s Printed Circuit Board (PCB)

A PCB is the motherboard of the boiler and is therefore located inside the unit itself. The PCB completes all of the communications between the various elements of the boiler, instructing tasks and performing safety checks in the background, so that if a fault is detected the safety mechanism kicks in to shut the boiler down to minimise any further damage to the boiler itself and protect the property.

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In scenarios where the boiler diagnoses that there is a fault with the PCB, the boiler may display an error code within the display window.

Such error codes will vary between the various brands and models of boiler and therefore it is always worth referring back to the boiler’s manual to check the meaning behind the error codes shown on your boiler.

Another common issue with PCB’s is that they fail completely and in which case, the display panel will be blank.

In this scenario, a Gas Safe engineer would need to be called out to investigate the matter further. In some instances, a PCB can be repaired and if so, the engineer will provide a quote to undertake the works, however usually the time needed to repair a PCB, plus any parts will usually be quite costly.

If the quote provided is fairly expensive, it may be worth considering replacing the boiler depending on the age of the boiler and if any warranty remains in place.

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Internal Boiler Fuse Fault

As discussed earlier, fuses can blow following a power surge and this is also true regarding the internal fuses within a boiler.

The process of a fuse blowing protects other boiler components from damage from a power surge however once an internal fuse has blown it will require replacing by a qualified Gas Safe Registered heating engineer, who will also undertake the necessary tests to ensure that all parts are working safely.

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An LED Fault

A fault within the LED lights can provide the false impression that a boiler has no power due to the display screen not lighting up.

A Gas Safe Registered heating engineer would confirm this diagnosis by undertaking some tests and can easily, replace the LED lights at a fairly reasonable cost.

Broken Boiler

If a Gas Safe Registered heating engineer assesses the matter causing the no power and provides a large quote to fix the boiler, it may be time to consider a boiler replacement as it is only deemed more economical to replace the entire boiler rather than spending lots on expensive parts for an ageing boiler.

Although a new boiler can seem very costly there are benefits to a new model including the energy savings, warranty and even new technology to manage the boiler remotely.

These days there are more methods than ever to purchase a new boiler either online, via large heating companies or by local suppliers, however, it is always essential that a new boiler is fitted by a Gas Safe Registered heating engineer.

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No Power to Boiler Summary

In this post, we have explored the common reasons that a boiler can either present as having no power, or actually having a loss of power.

Some causes can be easily identified and resolved however others will require a call out from a professional Gas Safe Registered heating engineer.

Should the engineer diagnose part failures and present large quotes, it may be worth considering opting for a new replacement boiler for both the benefit of energy savings from a modern boiler plus the peace of mind of the cover from a new warranty.

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