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What to do if your boiler breaks down

Image of a gas boiler

If you’re reading this, then the chances are that your boiler has stopped working – or, at the very least, you’re concerned that it might.

This guide will make the situation a little more tolerable, explaining exactly what to do if your boiler breaks down. Let’s get your central heating working again.

Table of contents

  1. Signs of a broken boiler
  2. Common checks if your boiler breaks down
  3. Check the electricity supply
  4. Check gas (or oil) supply
  5. Check the water supply
  6. Check the boiler pressure
  7. Check the thermostat and programmer
  8. Check for frozen pipes
  9. Check the pilot light
  10. Check for common boiler fault codes
  11. Still struggling with a broken boiler?
  12. Tips for coping without a working boiler
  13. How to prevent a boiler breakdown in the future

Signs of a broken boiler

As well as noticing a lack of heat or hot water within your household, there are some additional common boiler problems to look out for, including:

  1. Unusual whistling, banging, or tapping noises
  2. Higher than average gas usage indicates the boiler is not performing efficiently
  3. The pilot light or flames are orange/yellow, which should normally be blue
  4. It will show a high system water pressure instead of continuing at a steady pressure
  5. A leak has developed around your system’s pipes
  6. Your boiler won’t turn on

Common checks if your boiler breaks down

If you discover that your boiler has stopped working, most modern boilers will display an error code when something has gone wrong. Write down its error number before switching it off, and check if any other gas appliances such as ovens or hobs are working as normal. If not, this may indicate a problem with the gas supply.

Follow this checklist to diagnose the problem with your broken boiler:

  • Check the electricity supply
  • Check gas (or oil) supply
  • Check the water supply
  • Check the boiler pressure
  • Check the thermostat and programmer
  • Check for frozen pipes
  • Check the pilot light
  • Check for boiler fault codes

Check the electricity supply

Fuse box tripped

Firstly, ensure a switch hasn’t tripped in your fuse box, as this may impact your boiler. If you’ve recently had a power-cut, it may have caused the timer for your boiler to reset. Check that the clock display matches with the current time. If it doesn’t, it’s time to reprogram.

You can usually find the relevant instructions in the programmer manual; if you don’t have a hard copy available, tracking one down online is usually straightforward.

Prepaid meter

If you’re running a prepaid meter, then running out of credit will cause your supply to cut off and your boiler to stop working.

Ignition lead

The ignition lead is vital for your boiler to ignite. If, when trying to ignite your boiler, you hear clicking noises, then a faulty ignition lead or electrode may be to blame. You may also find that the boiler can ignite, but then quickly goes off again. If you have a newer boiler, a fault code will typically appear.

A Gas Safe Registered engineer will be able to test and replace these parts relatively cheaply.

Fan isn’t operating

Inside the boiler, there’s a fan which pushes harmful gases out of the boiler and into the flue. If the fan isn’t working, then the boiler will lockout and won’t ignite. Ask a Gas Safe Registered engineer if they can replace the fan in the boiler.

Check gas (or oil) supply

Gas valve

One of the most common reasons why a boiler fails to ignite is because of a problem with the gas flow into your boiler. There could be a blockage or damage which is impacting the gas flow.

Check other gas appliances to see if they’re operating correctly and ensure that the Emergency Control Valve by the gas meter hasn’t been turned off by accident. A Gas Safe Registered engineer will be able to check your gas supply and diagnose any issues for you.

Gas pressure

If there is too much or too little gas, then this can cause problems with your boiler. Your boiler is likely to display a fault code if the gas pressure is wrong. Ask a Gas Safe Registered engineer to test the gas pressure throughout your system.

If you think you can smell gas, it’s important that you contact the National Gas Emergency Service immediately on 0800 111 999.

Check the water supply

Check that your hot water supply is still turned on, if not then contact your water supplier to help investigate the problem.

Check the boiler pressure

A boiler will struggle to ignite (or won’t bother at all) if the water pressure is too low. You can check this by looking at the pressure gauge or boiler display. The reading should indicate that the water pressure is between 1 – 2 bars. If the reading is lower than 1 bar, the water pressure is too low.

You can try to repressurise the boiler by following the instructions in the boiler manual. If you can’t find it, you may be able to download your boiler manual online.

Check the thermostat and programmer

Your central heating programmer should be in the ‘on’ position and your thermostat set above room temperature. If the system works based on a timer, it may be that the clock has gone forward or backward and needs to be adjusted.

Check for frozen pipes

Due to the cold climate in the UK, it’s incredibly common that the weather can affect your piping system and frozen condensation can easily cause a blockage in the system. This blockage can cause the water to fill up the boiler and prompt a breakdown.

Whilst we advise contacting a qualified Gas Safe Registered engineer to assist you with frozen condensate pipes, you can try using a hot water bottle or pouring warm water onto the end of the pipe, before turning the boiler on and off again.

Check the pilot light

A pilot light is more common on older boilers and may go out due to a number of reasons. Firstly, you can attempt to ignite the pilot light yourself by following the instructions usually found in your boiler manual or located on the inside of the boiler door.

Remember, you should never attempt to dismantle your boiler or alter it in any way. If you can’t relight the pilot light you will need to call a Gas Safe Registered engineer.

Check for common boiler fault codes

Your modern boiler may show a fault code, helping you diagnose the issue quickly and efficiently. Some problems may be easy enough to fix yourself, whilst others will require the assistance of a Gas Safe Registered engineer.

If you don’t have access to your boiler manual, you should be able to locate it online. The following guides cover the most common boiler fault codes:

Still struggling with a broken boiler?

Due to the many safety devices on your boiler, there could be many reasons why your boiler won’t ignite. If you can’t see an obvious problem, then you will need a professional diagnosis.

Who to call when your boiler breaks down

As your boiler is a gas appliance, it’s essential to be safe when trying to resolve any issues. Remember, any work on the gas boiler itself MUST be done by a Gas Safe Registered engineer; it’s against the law for anyone else to do this.

Do not try to alter aspects inside the boiler yourself. If there is anything you are unsure about, it is best to seek the help of a professional.

Do you have boiler cover?

We’ve got a range of boiler cover options, from a standalone product, to those that include cover for other areas of your home, helping to keep your boiler and gas central heating working as they should be. Some policies even come with a free Boiler Service in the first year.

Tips for coping without a working boiler

If your boiler has broken down, keeping warm whilst you wait for it to be repaired can be a challenge. Here are some useful tips for coping without a working boiler:

  • Wear extra layers: If you want to stay warm whilst your boiler is being repaired, make sure you wear a few extra layers.
  • Eliminate draughts: Cold outside air likes to invite itself into your home through small cracks and gaps, so do some draught-proofing. Simple tasks such as closing your curtains or doors can help prevent heat from escaping from your home.
  • Use electric heaters: This alternative heating source can be a great temporary measure if your boiler breaks down. It can be an expensive alternative, so only heat the rooms you need.
  • Boil water: If you’re unable to get hot water from your central heating system, it’s worth boiling water in a pan or kettle instead.

How to prevent a boiler breakdown in the future

Regular boiler maintenance is key if you want to prolong the life of your boiler and stay cosy during the colder months of the year. Make sure you turn your boiler on regularly to keep it running efficiently and get into the habit of checking your boiler pressure.

It’s also important to book an annual boiler service, even if your boiler appears to be working fine.

If you’ve tried all of the above and your boiler still isn’t working, get in touch to arrange a visit from one of our Gas Safe Registered engineers who will be able to diagnose the problem and advise on the best solution.

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