How to bleed a radiator

Tuesday, 20th December 2022

With rising energy bills and freezing temperatures, it’s important to make sure your home is heating efficiently. One of the easiest and most effective ways to improve your energy bills and heating around your home is by bleeding your radiators. But how do you bleed a radiator we hear you ask?

If parts of your radiator have cold spots or you hear bubbling noises, this is the sign to bleed your radiators. The best part is, it’s really quick and simple to do. Let us show you how…

Why do you need to bleed radiators?

Naturally, when water is heated and cooled it produces air bubbles that stop hot water circulating around your radiators. More importantly it means your central heating system isn’t working efficiently and it can take longer to warm up your home. If left unresolved, this will put strain on your boiler and increase your energy bills.

How Long does it take to bleed a radiator?

It takes around 20-30 seconds to bleed a radiator. If you have a larger radiator or there’s lots of trapped air, this can increase up to one minute.

How often should you bleed your radiator?

To keep your radiators working efficiently, you should aim to bleed your radiators once or twice a year. This will ensure they produce plenty of heat throughout the year. But remember to feel for cold patches, particularly near the top, as this is a good indication to bleed your radiators.

To make sure you are ready for winter, we advise you bleed your radiators in the autumn as this will ensure your heating system is working well before the colder temperatures kick in.

Does bleeding radiators save energy?  

Bleeding your radiators will vastly improve the efficiency of your heating system resulting in a warmer home and cheaper energy bills.

What do I need for bleeding a radiator?

Bleeding a radiator doesn’t involve fancy gadgets. All you need is a radiator key or flathead screwdriver and an old cloth or jug to catch any water that escapes during the process.

How to bleed a radiator: a step-by-step guide

So, you should now have your radiator key and rags at the ready, but what’s next? Follow our step-by-step guide below to find out how to bleed a radiator.

Our top tip: if you are bleeding more than one radiator, start with the one furthest away from your boiler. If you own a two-storey property, we suggest starting with the downstairs radiators before moving upstairs.

  1. Make sure your heating is off and the radiators are cold. If left on the radiator will be too hot to touch, or hot water can splash out of the radiator.
  2. Hold an old cloth, or jug, under the bleed valve and insert the bleed key into the centre of the valve.
  3. Turn the bleed key anticlockwise about half a turn until air hisses from the valve.
  4. When water starts to trickle out of the valve, you have released all the air. It’s then time to turn the key clockwise to close the bleed valve. Be careful not to damage the valve by overtightening.
  5. Repeat this process on other radiators around the house that need attention, working your way back to the boiler.
  6. Turn your heating back on and check if your radiators are heating up your home efficiently.

So now you have the tools and knowledge to go out there and bleed your radiators. Your home should be ready to take on the winter weather while saving on those all-important energy bills. But, did you know all our homes come as EPC A/B standard? That means you could save on average around £2,200 on energy bills a year. Take a look around our developments and you could be saving money on your energy bills with a Castle Green home.

Please consult a professional if you intend to carry out DIY you’re not fully confident in doing yourself. We accept no responsibility (including loss, damage or injury) for your use of the advice on this blog. 

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