How to Bleed a Radiator: A Step By Step Guide | Plumbworld

Keeping your home warm and cosy all year round is essential but when your radiators aren’t working to their full capacity, you might be left wondering what’s wrong. One of the most common issues with radiators is when they’re not bled regularly, leading to cold spots and even your whole heating system working inefficiently.

Keep reading to find out how to bleed your radiators and when this task should be completed.

What Does Bleeding a Radiator Do?

Bleeding your radiators helps to get rid of pockets of air that build up and in turn, prevent hot water circulating around the radiator correctly. Regularly bleeding your radiators will help to keep your heating system running smoothly.

How Do I Know If My Radiators Need Bleeding?

If you’re wondering how you will know when your radiators need bleeding, you’re not alone. Bleeding your radiators is something most of us put off but it can be a quick straightforward task when carried out regularly.

As a general rule of thumb, it’s a good idea to bleed your radiators at the end of the summer, helping to give your heating system a fresh start before it’s turned on again for the cooler months.

However, you could see signs that your radiator needs bleeding, such as hearing gurgling noises or finding your radiator takes longer to heat up than usual. One big tell-tale sign that your radiator needs to be bled is the bottom of the radiator feeling warm but the top feeling cold to the touch.

If the top of your radiator feels cold while the bottom is still warm, this is normally down to a build-up of trapped air in the top of your radiator. If this is the case, bleeding your radiator should fix this issue.

What Tools Will I Need 

Before you start the task of bleeding your radiator, you will need the following tools to hand:

  • A radiator key or a flathead screwdriver
  • A towel or cloth to catch any leaks
  • A container or jug to collect any excess water

How to Bleed a Radiator

Once you’ve bled a radiator a couple of times it becomes like second nature, making it a quicker task each year. Keep reading for details on how to bleed your radiators:

  • The first thing you need to do is turn off your central heating system and wait for your radiators to cool completely.
  • Next, find the bleed valve. This is usually located at the top right of the radiator and is round in shape with a square nut in the centre.
  • Before inserting the bleed key, make sure your cloth or towel is ready underneath the valve. This will help to catch any small leaks. However, make sure to have an old tub or container on hand to catch any large leaks if necessary.
  • Insert your radiator key and slowly turn it anticlockwise until you hear a hissing sound, which will be the air escaping. This is when you might start to get some water leakage.
  • Once any air has finished escaping and you no longer hear a hissing sound, quickly turn the valve clockwise until fully closed. Make sure not to tighten it too much, but enough to prevent water leakage.
  • Clean away any water and repeat the process with your other radiators.

What to Check After Bleeding Your Radiator

Once you have bled your radiators, it’s essential to perform a couple of checks to ensure your heating system is once again running as it should be:

  • Ensure all radiator valves have been tightened correctly and you have no leaks.
  • If your radiators felt cold to the touch before you bled them, be sure to check they’re now heating up evenly across the whole unit.

Best Practices of Bleeding a Radiator

To make sure the process of bleeding your radiators goes as smoothly as possible, take a look at our handy tips for bleeding a radiator below.

It’s always a good idea to bleed your radiators every year, at the end of summer, to ensure they’re running as efficiently as possible in time for the colder months.

Keep an old towel and container accessible when bleeding your radiators to catch any water and prevent damage to your walls and floors.

Make sure to turn your central heating off well in advance of bleeding your radiators, to ensure the system has had time to fully cool down.

If you are unsure about the process or don’t feel fully comfortable bleeding your radiators, make sure to get help from a professional.

Discover Plumbworld's Wide Variety of Radiators

At Plumbworld, we stock a wide range of radiators, from classic panel radiators to more contemporary designer models, all perfect for keeping your home warm and toasty.

If you’re looking for a traditional option, then our traditional column radiators might be the perfect choice. However, if you’re looking for something sleek and stylish, why not take a look at our matt black, flat panel radiators? Visit our website today to view our full range of radiators.

If you found this post useful, you might also like - A Step-by-Step Guide to Changing a Radiator Valve - Heating Advice: How to check your radiators - How to Fit & Replace a Radiator.


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