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How To Bleed A Radiator?

The output of heat from your radiator will be considerably reduced if there is air trapped in the pipes. It will usually not be long before you notice that your home is not warming up as quickly as usual even when the heating is turned on. There are several signs that could indicate it is time to bleed your radiators. These include:

The Home Isn’t Warming Up:

If your central heating is not providing adequate heat and you are left cold even after switching the heating on, there’s no need to panic. Chances are that bleeding the system will be all it takes to get your central heating working as normal once again. If you’ve noticed that your radiators are warmer on the bottom than they are at the top, bleeding will usually work. Air can get stuck in radiator pipes during any time of the year, but it’s best to bleed the system during autumn, so that you’re ready to face the winter.

Cold Spots:

In some cases, the radiator will heat up but there will be cold spots on the radiator. If one or more areas of your radiator feel cool to the touch even when the heating is switched on, this is usually a sign that the system is in need of bleeding. This will allow the air to be released and your radiators should be consistently warm all over as a result.

Damp Spots:

Damp spots around the home is a sure sign that something might not be working as it should with your central heating. This can often mean that radiators are not working as efficiently as they could be, and the home is colder than usual. Moisture from the air settling on cold surfaces leads to damp, and if not dealt with quickly can lead to serious damage from mould patches. If bleeding the radiators does not prevent damp patches in the future, this could be a sign of a more serious problem and you should contact your property manager as soon as possible.

Radiators are Cold:

A radiator that stays completely cold even when the central heating is switched on is usually indicative of a problem. After checking that the radiator itself is switched on, bleeding the radiator should be the next step to try and solve the issue. However, an entirely cold radiator is often a sign of a bigger problem with your central heating. if bleeding the radiator doesn’t cause it to warm up as it should, contact your property manager who can help by sending an engineer to check your heating system over.

Noisy Heating System:

Noise when the central heating system is warming up, such as a soft ticking or knocking sound, is not uncommon, especially in older systems. But if the sound of your central heating system turning on is causing a real disturbance to your home life or you’ve noticed gurgling sounds coming from your radiators, this could be a sign that they need to be bled. Bleeding the radiators can help to solve this problem as it can often be caused by excess air in the pipes. If the problem continues after you have finished bleeding the radiators, call your property manager who will send an expert to take a look.

How Do I Bleed a Radiator and How Often?

Most of the time, bleeding the radiator is not something that people think about until one of the above problems arises. However, waiting for a problem to occur means that there might be some damage to the radiators and heating system that you are unaware of. In addition, as the air continues to build up inside the radiator pipes, your heating system may be working less efficiently and costing you more money in utility bills than is necessary. Because of this, it’s a wise idea to bleed radiators on a regular basis. The best time to do this job is before the heating season starts, which is usually around autumn time. Before the winter, it’s a wise idea to check and carry out basic maintenance on your central heating system to avoid inconvenient problems that may leave you without central heating during the cold winter months.

How Do You Bleed A Radiator in a House and Will All the Radiators Need Bleeding?

Whether you will only need to bleed one radiator or all of them will depend on the issues that you are experiencing. Chances are that if you’re having issues with one radiator, the others will soon follow, especially if all radiators in your home are used for heating. If you’ve noticed cold patches or other problems with one radiator, it’s worth bleeding the others in your home to release any excess air and help your heating system run more efficiently.

Step-by-Step Guide to Bleeding Old Radiators:

Bleeding a radiator is a relatively simple process that does not usually require the help of an expert. You can do this yourself at home by following these steps:

How To Bleed A Radiator, By Greater London Properties

If a radiator is cool at the top and warm at the bottom you will need to bleed the radiator. Trapped air in the system prevents the heated water from circulating around the radiator fully and so the radiator often feels warmer at the bottom.

If the whole radiator is cold, check that the radiator valve is turned up (see diagram below). If more than one radiator is cold, the whole heating system may need to be checked by a heating engineer. Call your property manager during working hours.

Turn off the heating system before bleeding otherwise the pump might draw more air into the system. You will need a special radiator key, available from most DIY and hardware shops. You will also need a rag or cloth and a bucket or bowl.

Bleeding a radiator is a relatively simple and safe procedure. All radiators come with a ‘bleed key’(see diagram below). There will be a protrusion near the top of the radiator, on one side, called the bleed valve. You will need to open this valve a small amount to allow the air to escape from the top of the radiator whilst not allowing the water to flow out. Take care when turning the valve, have an old rag to shield your hand and a small bowl to catch any small drops of water which may escape.

First turn off the heating or you could import more air into the system. Fit the bleed key into the bleed valve and carefully turn it counterclockwise only a tiny bit, usually just a quarter or half turn. The air will start escaping with a hissing sound similar to a bicycle tire. When water begins to dribble out, all the air is purged, and you can gently return the bleed valve to its previous position. You should then remember to turn the heating back on and check that there are no leaks from the radiator valve.

Hopefully this article has helped you with your question ‘How to bleed a radiator’. For more helpful articles and videos, please look at our FAQ Property Management section on our website.

If you would like to know more about Greater London Properties In House Property Management please call us on 0207 734 4062. We work with all our tenants to keep costs at a minimal and solve any issues within 24 hours. All our contractors are within 1 mile of our branches and every Landlord has a dedicated Property Manager with their direct office line, mobile phone number and email.  Our costs are absolutely transparent and we  get three quotes before moving forward with any work.

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