How to Bleed a Radiator

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How to bleed a Radiator?

Radiators need bleeding when air pockets get trapped inside them. The trapped air pockets prevent hot water from effectively circulating the whole radiator which creates cold spots so, less heat is given out. Therefore, it is likely it will take more energy to heat your home and your energy bill could be higher than normal.

It is easy to release the trapped air pockets by simply bleeding your radiators. Bleeding your radiators will release the air pockets allowing the hot water to effectively circulate your radiator, emitting more heat into your home and potentially saving you money on your bills. This is because your radiators and boiler work alongside each other so, you are paying for the same amount of energy and making your home more energy efficient.

Follow these 10 simple steps to find out how to bleed a radiator:

  1. Switch on your central heating – Switch your central heating onto full and wait for the radiators to reach their maximum temperature.
  1. Identify which radiator needs bleeding – Carefully touch each radiator in your home feeling for any cold spots. If you find that more than one radiator needs bleeding, then bleed the radiators which are furthest away from the boilers first.
  1. Switch off your central heating – Before bleeding your radiators it is important you switch off your central heating system and allow your radiators to cool down fully before bleeding them.
  1. Find a radiator key – To bleed your radiators you need to find something which will open the radiator’s “bleed valve”. A radiator key which can be found at a local DIY store will do this, but some modern radiators have valves which require a flathead screwdriver. Before bleeding your radiators make sure you have the radiator key or a screwdriver which is able to open the valve on every single radiator. You will also need a cloth or kitchen roll to catch any drips.
  1. Locate the bleed valve – The bleed valve is located at the top of your radiator at one of it’s ends and will look like a round hole with a square inside it.
  1. Put a cloth underneath the valve – Put the cloth or kitchen roll underneath the valve so, you are ready to catch any water.
  1. Open up the bleed valve – Insert the radiator bleed key into the bleed valve. Carefully turn the key a quarter of a turn anti-clockwise when the air starts to escape you will hear a hissing sound as the air escapes.
  1. Close the bleed valve – Once the air has been released and the hissing sound stops, the valve will then start to release water. This means all the air has left the radiator and you can now close the valve. Turn the key a quarter of a turn clockwise to close the valve. Be careful not to over tighten as this could damage the valve.
  1. Repeat the process – To bleed the rest of the radiators in your home you will need to repeat the process.
  1. Check the pressure of your boiler – Once all the radiators with trapped air pockets have been bled you will need to check the pressure of your boiler gauge. If the pressure is too low then you will need to re balance the radiators. However, if the pressure is normal you can switch back on your heating to check that there aren’t any cold spots.

If after bleeding your radiators you still find there are cold spots in your radiators then you may need to a Gas Safe engineer to have a look at them for you. Please call us today on 0330 3530 365 and one of our friendly helpdesk advisers will be more than happy to help.