Do your radiators need bleeding? These top tips will get them heating evenly

Have you woken up to a mediocrely warm home again? Or did that creaking noise stop you sleeping comfortably? If so, it’s time to bleed your radiators

Princess aged gold vintage radiator
(Image credit: Castrads)

Do you think you need to bleed your radiators? It’s that time of year when you may start noticing glitches in your central heating system. It’s cold, and if your radiators aren’t working properly, the chances are that you need to let trapped air out of them by bleeding them. This is an essential part of making sure that your central heating is working efficiently and not wasting you any money.

How do you know when your radiators need bleeding? Well they may not be heating evenly, with cold spots at the top or bottom. This is because air is trapped in the system and the hot water is not filling the whole radiator, leaving it less efficient. If your rooms aren't getting warm enough, or are taking too long to heat, this is most likely the reason why. Fortunately, bleeding them is an easy job that pretty much anyone can do.

The quicker you do the job, the quicker your home will be warm again, and whether this is a first time DIY for you or if you just want a refresher on how to bleed the radiators in your home, this is all you need.

Essential equipment:

You will need:

  • A radiator key to open up the vent valve
  • An old rag, towel or cloth to catch the drips
  • We would – from experience – also recommend a largish tub also to catch any bigger leaks

Bleeding radiators sequence:

1. When your heating is switched on, check which radiators need bleeding and use our more in depth guide if you need help with this.

2. Turn the heating off again, let the radiators cool.

3. Prepare for drips, laying towels around the radiator.

4. Insert your radiator key into the bleed valve (nipple) which is the round hole with the square inside. It’s usually located at the top or the side of the radiator. It should lock into place easily.

5. Turn the valve anti-clockwise – a quarter or half turn will suffice – so that the air can escape. Note that the escaping air may be hot so keep a short distance and expect a hissing noise, this is completely normal.

6. Continue this process until the air stops. You will know it’s done when just water drips from the radiator.

7. Seal the bleed valve again by tuning it clockwise making sure to not over-tighten it.

8. Action this on all your radiators and Bob’s your uncle.

Pro tips:

  • It’s recommended to start on the ground floor of your property and to work your way up, as the air moves its way up the system
  • Some modern bleed valves will release water very quickly so you should turn the valve key with care and be ready to close it quickly