Radiator bleeding and maintenance provided by Hydra Plumbing Services Ltd

Benefits of bleeding your radiators:

  • Bleeding regularly prevents heating issues.
  • Rooms will warm more effectively and efficiently.
  • Radiators will work more quietly.
  • Helps maintain the life of your heating system overall.

When should you bleed your radiator?

If you have never bled your radiators, or have not bled them in a very long time, then it is a good idea to try and bleed them as soon as possible – even if they are not showing signs listed below.

If you think your radiator may need bleeding, start by looking out for these signs. Your radiators could need bleeding if:

  • your radiator has cold spots when turned on.
  • there is a cold spot at the top of a radiator.
  • the whole radiator is cold.
  • you begin seeing odd stains such as damp patches or mould on the walls, especially in rooms not often used.
  • there are odd noises such as rattles or gurgles coming from your radiator.

If you spot any of the signs listed above, then you should consider bleeding your radiators, as it is highly likely there is air trapped inside.

(Some of these symptoms could be an indication of other problems, but before anything, you should try bleeding the radiator(s) first.)

How long will it take to bleed a radiator?

A good rule of thumb is that a radiator will take around 20 to 30 seconds to bleed. This may vary due to things such as the size of your radiator, and the amount of air trapped inside.

An easy-to-follow guide to bleed your radiator:

You know what to look out for and how long this might take, so now here’s a quick guide to help you bleed your radiators.

First, here are the tools you’ll need:

  • Radiator key
  • Bucket or bowl to catch any water
  • Cloth to clean up any spilled water
  • Gloves sturdy enough to protect you from scolding hot water

Safety Warning – The water inside radiators can be very hot, so take precautions not to scold yourself. Wear protective gloves / clothing, and consider laying down a towel or sheet to look after your floors.

Now it’s time to bleed your radiators:

1 – Turn off your heating and leave the radiators to cool down. When they’re not too hot to touch, move on to the next steps.

2 – Find the radiator bleed valve, this is usually at the top corner of a radiator, look for a round hole with a square inside. Then put a cloth or bowl below it to catch any water.

3 – Insert the radiator key and twist anti-clockwise. As the air escapes, you’ll typically hear a hissing sound.

4 – When the hissing stops and water starts to leak out, turn the radiator key clockwise to close the valve.

Repeat this process for any of the radiators that need bleeding in your home.

When you’ve finished bleeding your radiators, be sure to check the boiler pressure, as bleeding radiators can sometimes cause the pressure to drop. If discover you have low boiler pressure, you will need to repressurise your boiler.

    Common Questions:

    How often should you bleed radiators?

    You should do a full check every couple of months, and double-check your radiators before winter arrives.

    Can you bleed radiators when the heating is on?

    Do not bleed any radiators when the heating is turned on. This is because it will be too hot to touch and if hot water is released it could potentially burn you. Also, letting out air when the pump is running will only draw more air into the system from elsewhere.

    How do you know if bleeding a radiator worked?

    After you’ve finished bleeding the radiator(s), close the radiator valves. Now it’s safe to turn your central heating and hot water back on. If the bleeding has been successful, your radiators should begin heating up within a few minutes, and the heat will be even across the radiator.

    You can also check the pressure gauge on your boiler, it should read between 1 and 2 bars.

    Radiators still cold after bleeding them?

    If you’ve tried fixing it yourself, and it just doesn’t seem to be working, you may need an extra pair of hands to get this issue sorted.

    For a hand diagnosing and fixing the issue, get in touch with Hydra Plumbing Services Ltd

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