Preparing your boiler for winter - 9 key steps
Tuesday, 9 December 2025
As the nights get darker and the temperature plummets, your boiler will very swiftly become the most important device in your house, no matter how much you love your TV. So it's vital that you look after your boiler and ensure that it's in the best condition to heat your home through another chilly winter.
Here we look at the nine key steps you can take
1. Restart your heating in autumn
The best time to test anything works properly is before you really need it. And so it makes sense to switch your heating back on in early autumn, possibly even before your home is feeling especially chilly. This will give you the chance to discover any issues or gremlins and get an engineer in to remedy them. Leave it any later and you might regret it as you find yourself wearing your hat and scarf indoors.
2. Test your thermostat controls
As part of the restart phase (see above), you should make sure that it's not just your boiler working properly but also every other component related to it. That includes your thermostat, which you use to set your temperature and schedule heating times, and also your thermostatic radiator valves (known as TRVs), which control the temperature of individual radiators. For households with inquisitive small children, it's not unusual for these to have been played with over the summer, so you might want to check they're set correctly.
3. Bleed your radiators
Trapped air in radiators can cause your system to run inefficiently. When you switch your heating back on, listen out for any unusual gurgling or banging or feel around for any cold spots, as this is an indication of air in the system. Bleeding your radiators should get rid of those meddlesome pockets of air.

4. Check boiler pressure
Bleeding your radiators is likely to reduce pressure, so the next step is to check your pressure gauge. Your boiler's pressure should usually sit between one and two bars (your engineer should have set a small red dial at the desired reading), so if it appears below this measurement, you might need to top-up using the filling loop. Don't overfill, and if you discover that the pressure drops regularly, you could have a leak.
5. Clean the area around your boiler
You've heard of a spring clean, but your boiler will certainly welcome an autumn one, too. Keeping the surrounding area free from clutter will not only provide enough room for your engineer to get in should access be required, but it'll also give you a better chance of spotting any problems such as leaks or corrosion. Make sure to inspect the flue for blockages, debris, or signs of damage, and ensure good ventilation.
6. Test your carbon monoxide alarm
On the subject of ventilation, it's vital that you test your carbon monoxide alarm before you begin using your boiler on a daily basis. If it doesn't work, don't delay in getting a replacement. And if you don't have one, make it a priority. There are over 400 hospital admissions per year in England due to carbon monoxide poisoning.
7. Insulate your pipes
Frozen pipes in winter can cause untold damage to your boiler and home. If you have any exposed pipework, especially any exposed to the outdoors, do your best to insulate them using foam lagging.
8. Schedule an annual service
If any of the above sounds a little daunting, then fear not. By far the best way to look after your boiler before its busy winter is to schedule an annual boiler service with Gas Safe registered and experienced engineers. They'll ensure your boiler is in optimal health and diagnose any issues early on. It's also a good idea to have your gas engineer's up-to-date contact details close to hand so that they're easy to find in an emergency.
9. Contact Koziwarm
Here at Koziwarm we've been servicing and installing boilers since 1981. A family-run business based in Wallsend, we're perfectly located to serve the whole of the North East. Our team of experienced heating engineers are all Gas Safe registered, so don't hesitate to contact us today for any boiler servicing, repairs, or installation requirements.
Book An Appointment
If you need your boiler serviced, repaired or require a new boiler installed, then contact the Koziwarm team today.
Our friendly team will book you in for a time that suits you best.
Call 0191 262 8000