How to Repressurise a Heating System - How to Top Your Boiler

Have you ever been in the middle of a winter chill, and suddenly your heating system lets you down? As a plumber, I've seen this happen time and time again. Low boiler pressure can be a real headache, but it's something you can easily fix. In this post, I’ll walk you through how to repressurise your heating system and top up your boiler like a pro. First off, it’s essential to know that maintaining the right pressure in your boiler is crucial for it to operate efficiently. Usually, your boiler should be running at around 1 to 1.5 bar. If you find that the pressure falls below this range, don’t panic. Repressurising your system is a straightforward task that can save you a call to the professionals. Start by locating the filling loop on your boiler. This is usually a silver, flexible hose with two valves at either end. Once you’ve found it, make sure both valves are closed before you begin. Next, slowly open the valve on one end of the filling loop, and allow water to flow into the system. Keep an eye on your pressure gauge while doing this—once it reaches the desired level, close the valve to stop the flow. After you’ve topped up the pressure, it’s vital to bleed any radiators that may have air trapped inside. This ensures hot water circulates properly throughout your heating system. Just grab a radiator key, turn it counterclockwise, and let the air escape until water starts to drip out. Easy peasy, right? If you’re ever unsure or feel uncomfortable doing this yourself, don’t hesitate to call a professional. However, with a bit of practice, you’ll have the confidence to tackle this issue whenever it arises. Check out the video I’ve embedded above for a visual guide that will walk you through the process step by step. It’s packed with tips to help you make this job as seamless as possible. Remember, a well-maintained boiler is a happy boiler, so keep that pressure topped up and your home warm this winter. Happy plumbing!