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How to Bleed a Radiator

How to Bleed a Radiator

No matter how expensive, technical or pretty your radiator is, chances are that you’ll need to bleed it at some point. As you use your heating system, air can get trapped inside your radiator and result in the heat not being distributed as evenly, and efficiently, as usual. This results in the need to bleed it. The reality of owning a radiator is that with general use, air being trapped is a natural part of running a radiator and therefore is an inevitable part of maintaining your radiator. If you’re a newbie to radiator maintenance or a radiator pro looking for a reminder of how to get a perfect radiator bleed, you’ll find everything you need here.

What is bleeding a radiator?

When you bleed a radiator, you are releasing air that gets trapped inside the radiator and stops heat from circulating around it properly. The process itself is simple and just requires loosening the radiator bleed valve until the trapped air and water can come out of the radiator.

When should you bleed a radiator?

You feel cold spots

You’ll need to bleed a radiator when it isn’t working efficiently. You can tell if your radiator isn’t working properly if it isn’t distributing heat evenly throughout the radiator and you can feel some cold spots. There may even be whole areas of your radiator that aren’t getting any heat, particularly towards the edges.

It makes noises

Another sure sign you need to bleed your radiator is when it makes clunking and groaning sounds when you turn your heating on. So if you’re wondering “why is my radiator making a noise?” it’s probably because it needs bleeding.

Why bleed a radiator?

The most obvious reason for bleeding your radiator is to keep it working smoothly and keeping your home toasty all year round. Releasing the air that can build up inside your radiator and decrease its effectiveness will keep it working at its best. This is because this trapped air can lower the efficiency of heat distribution, leaving you with a radiator with cold spots. But bleeding your radiator when needed also provides an extra benefit of saving you money. When your radiator isn’t heating up properly, you will put your heating on more frequently, or at a higher temperature. Doing so will only wrack up your energy bills and result in you spending more money on heating. In addition to the money-saving benefits from effectively maintaining your radiator, keeping your household energy efficient is great for the environment too as it keeps your energy usage down. By maintaining your radiator’s functionality, you’re indirectly doing your bit for the planet. (For more ideas on keeping your heating green, check out our piece on aluminium radiators, are they worth it?.)

How to bleed a radiator

Before we get into the process of bleeding your radiator, you need to make sure you have the right kit. The most important tool when it comes to bleeding your rad is the radiator bleed key. This may be something you’ll find after a rummage around in a draw, but if you don’t have one to hand, no worries. You can get a FREE bleed key from us at UK Radiators, just let us know where to send it

What you’ll need:

  • A radiator bleed key (And if you don’t already have one, we’ll send you one for free!)
  • A container or towel to place under the radiator
  • cloth or towel to soak up any water leakage

1. Turn on the central heating

The first step is to turn on your heating to full power so that you can locate the radiators that need bleeding.   Turn on the central heating  

2. Feel all the radiators in your home

This is how you’ll identify which radiators need bleeding. Feel for cold spots and listen out for any weird gurgling sounds coming from them.

3. Switch off the heating and wait for the radiators to cool completely

So now you know which radiators need bleeding, you’re going to need them to be completely cool before you can bleed them. So let them cool off completely before you jump into the bleeding process.

4. Grab your supplies

Every radiator comes with a radiator key, but if you can’t find yours, any DIY shop will sell one. Some more modern radiators actually work with a flat-headed screwdriver, but you’ll have to check yours to make sure.

5. Find the bleed valve

The bleed valve will be at the top of the radiator on one of its ends and will look like a round hole with a square inside it. This is where you’ll be releasing all that built up air and water, so place your old towels underneath it with the container on top to catch any excess water coming out.   Find the bleed valve  

6. Loosen the bleed screw and wait for the hissing to stop

To bleed your radiator you just need to turn the bleed screw anti-clockwise. Be careful though, as a quarter to half a turn will be enough. It’s important to not open the valve fully because once you bleed air from the radiator water will come rushing out. Once the hissing sounds of excess air and water coming out of your radiator stop, you can retighten the valve and clean up any leakages.   Loosen the bleed screw and wait for the hissing to stop  

7. Turn on the heating again

Once you’ve bled your radiator, simply turn the heating back on and enjoy the fruits of your labour! We want our customers to take control of their heating and save money wherever possible - that’s why we’re offering a FREE radiator bleed key to anyone who needs one. Sound good to you? Then head over to our site and get yours ordered now. And if all of this sounds like too much or you don’t fancy yourself a DIY pro, there’s an even simpler option. Our auto-bleed radiator bleed valves are just the thing you need. With these magic little valves, you won’t even have to worry about bleeding your radiator as these valves do it for you, all whilst keeping your radiators in good working order. For more guidance and home heating tips, head over to our advice centre.

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