Bleeding a radiator is a straightforward process that helps ensure your heating system runs efficiently, especially during those cold UK winters. Here's a comprehensive guide to help you through the process.
Steps to Bleed a Radiator
- Identify which radiators need bleeding: Turn on your heating and check each radiator for cold spots, particularly at the top or in the middle. Random pockets of cold spots indicates that air is trapped in the radiator / plumbing which prevents proper heat distribution.
- Turn off / cool down your boiler: Before you start, make sure your heating is turned off and the radiators have cooled down to avoid the risk of burns from hot water. Trust us, you don’t want hot water spurring out everywhere.
- Gather a Bleed Key or a Flat-Head Screwdriver: You'll need a radiator bleed key (or a flat-head screwdriver for some modern radiators), a cloth, and a container or towel / tissue to catch any water that may drip out.
- Locate the bleed valve: This is typically found at the top of the radiator on one of its ends. It looks like a round hole with a square inside it.
- Bleed the radiator: Place your cloth and container under the bleed valve. Use the bleed key to turn the valve counterclockwise, but only slightly. You should hear a hissing sound as the air escapes. Once water starts to flow out steadily, indicating that all air has been released, tighten the valve back up. You’ll be able to hear water burbling inside the radiator as the air escapes. This is normal.
- Repeat as necessary: Move through your home, bleeding any radiators that need it, starting from the one furthest from your boiler and working your way back.
- Check boiler pressure: After bleeding your radiators, your boiler may have lost (more than likely) pressure. Please check your boilers pressure and if it has dropped too low (usually less than 1.5 bar), you’ll need to repressurise your boiler and top it up before turning on your heating again.
Finally, turn the heating back on. With all radiators bled and the boiler pressure checked, your radiators should now heat up more evenly and efficiently.
Why Bleed Your Radiators?
Bleeding your radiators can improve their efficiency and heat distribution throughout your home, ensuring it stays warm when you need it most. Air trapped in the system can cause radiators to have cold spots or make noise, indicating that bleeding is necessary. Regular maintenance, including bleeding, helps save on energy costs and extends the lifespan of your heating system.
Leading onto - why does air get trapped into the boiler system?
Briefly, air can get trapped into the system and affect radiators for numerous reasons. Introduction of new water - i.e. when topping up your boiler or replacing parts/servicing, water naturally contains air, which can become trapped in the system.
Likewise a leak in the system could be letting air come into the pipework somewhere which is causing air to get trapped.
Plus, general heating and cooling cycles of your system can cause air to be released from the water and get trapped in high points, like the tops of radiators.
We can go into this in more detail in a follow up article.
For now, I hope this post helps you relieve the cold spots in your radiators by effectively bleeding them, and ensuring your heating system is working in tip top shape.
If you have any questions, please feel free to get in touch with us where one of the team will be more than happy to help you.