There’s never a good time for your boiler to stop working, especially during a cold snap or right before guests arrive. Whether it’s an icy morning or a chilly night, losing heating or hot water can quickly turn into a stressful situation. Fortunately, knowing what to do when your boiler breaks down can save you time, money, and unnecessary panic.
In this guide, we’ll walk you through the essential steps to take when your boiler fails, how to stay warm in the meantime, and when it’s time to call in a professional. This information is especially useful for homeowners and landlords across the UK, where reliable central heating is a must.
1. Stay Calm and Assess the Situation
It’s easy to panic when you realise your boiler isn’t working. But the first thing you should do is take a moment to stay calm. Not every boiler issue is a disaster, and some can be resolved quickly without specialist help.
Here’s a checklist to run through:
- Is the boiler display on? If not, it might be a power supply issue rather than a boiler fault.
- Do you have gas and electricity? Make sure your utility supplies haven’t been interrupted.
- Is your thermostat set correctly? A simple temperature mismatch can prevent your heating from kicking in.
- Has the timer or programmer changed? Power cuts and daylight saving changes can affect boiler timers.
By ruling out the obvious, you may find a quick fix or at least narrow down the issue.
2. Check Boiler Pressure and Reset if Safe
Most modern boilers display their pressure reading on a small dial or digital screen. The ideal range is usually between 1 and 2 bars. If the pressure is too low, your boiler might shut down as a safety precaution.
Here’s what you can do:
- Top up the boiler pressure using the filling loop (usually a silver flexible pipe under the boiler). Instructions are often in the manual or online.
- Reset the boiler after topping up, if your system requires it.
Important: Only perform these steps if you feel confident. If you’re unsure or if the boiler leaks water during this process, stop immediately and call a qualified engineer.
3. Bleed Your Radiators
Air trapped in the radiators can prevent your heating from working properly, even if the boiler itself is fine. Bleeding radiators is a quick DIY job that can help get the system running more efficiently.
What you’ll need:
- A radiator key (available at most DIY stores)
- A cloth or small container to catch drips
Steps:
- Turn off the heating and allow radiators to cool.
- Use the key to open the bleed valve (usually found at the top corner of the radiator).
- Let the trapped air escape—you’ll hear a hissing sound.
- Once water starts coming out, close the valve.
Check the boiler pressure again afterwards, as bleeding can lower it.
4. Look for Error Codes
Modern combi and system boilers often have a digital display that shows an error code when something goes wrong. These codes help identify the issue, such as ignition failure, sensor faults, or pressure problems.
Refer to the user manual or the boiler manufacturer’s website to understand what the code means. The user may reset some minor faults, but a certified Gas Safe engineer should handle anything more technical.
5. Keep Warm While You Wait
If your boiler breaks down and isn’t fixable right away, it’s important to keep yourself and your household warm, especially if it’s freezing outside. Here are a few practical tips:
- Layer up: Wear thermal clothing, hats, and socks indoors.
- Use portable heaters: Electric fan or oil heaters can warm a room quickly.
- Close doors: Keep warmth contained in one room rather than heating the entire house.
- Hot water bottles: Simple but effective, especially at night.
- Cook meals: Using the oven or hob adds extra warmth to your kitchen.
These measures can help you stay comfortable until the boiler is back up and running.
6. When to Call for Emergency Help
Not every boiler issue can be resolved with DIY checks. If you notice any of the following, it’s time to call in the professionals:
- No power at all to the boiler
- Leaking water or unusual smells
- Strange noises (banging, whistling, gurgling)
- No heating or hot water despite resetting
- Frequent pressure drops or unexplained shutdowns
- Error codes you don’t understand or can’t clear
And of course, if you detect the smell of gas, leave the property immediately, do not switch anything on or off, and call the National Gas Emergency Helpline at 0800 111 999.
If you’re based in Scotland, don’t wait and call for emergency boiler repair in Glasgow.
7. Prevent Future Breakdowns
Prevention is always better (and cheaper) than a cure. Here’s how you can reduce the chances of being left in the cold again:
- Annual boiler service: This keeps your system running efficiently and safely.
- Lag your pipes: Insulate outdoor pipes to prevent them from freezing and causing pressure issues.
- Check pressure regularly: Keep an eye on the dial and top up as needed.
- Bleed radiators yearly: Air buildup can strain your boiler.
- Get an upgrade: If your boiler is over 10–15 years old, replacing it could save you money on energy bills and emergency repairs.
Final Thoughts
A boiler breakdown can be inconvenient and uncomfortable, but knowing how to respond can make all the difference. Simple checks might resolve the problem, but if not, it’s best to get help from a qualified professional as soon as possible.
By acting quickly and staying informed, you’ll keep your home warm, safe, and stress-free—whatever the weather brings.
