How To Bleed A Radiator in 8 Easy Steps

Are your radiators cold even when the heating is on? Our how-to bleed a radiator in 8 easy steps will get your home warm again in a super quick time.

Bleeding your radiators regularly will increase the efficiency of your central heating and will help to reduce your energy bills.

Should I bleed my radiators?

Radiators become less efficient when they have pockets of air trapped in them which causes cold spots in your radiators.

Bleeding your radiators will release the trapped air allowing the hot water to circulate freely heating your home more effectively. Even the best combi boiler can work ineffectively with trapped air in radiators.

If you do all this and your radiators are still patchy then you may need to invest in a power flush or chemical flush. This will clear the system of any sludge

Why would you want to bleed a radiator, anyway?

Radiators that have trapped air need to be drained. The trapped air prevents warm water from circulating around the radiator. This can cause the radiator to become cold at its top but warm at its bottom.

This means that your central heating system isn’t operating efficiently, and your room may take longer to heat up. This can lead to higher bills and cost you more money.

If your radiators are making loud, clanking, or gurgling sounds, you might need to release the trapped air.

You also may get an error code for your boiler that is related to any trapped air in your radiators, such as the Ideal F1 fault code.

Even if your radiators are functioning properly, it is recommended to bleed them once per year.

When to bleed your radiators

If the radiator’s temperature is hot at the bottom but cold at its top, it may be air trapped within. You will need to clean it. These are other signs your radiator may need to be bled:

The entire radiator is cold

Although this isn’t as common as a radiator with air trapped inside, it is an indication that your radiator needs to be repaired. If there is trapped air in the pipes, it can restrict the flow of hot water into the radiator. This could lead to bigger problems down the line. To get things back on track, check your thermostat, but if not, you should contact your local heating engineers.

Radiator cold at The Top

This is the most obvious sign that your radiator needs to be bled. It means that hot water has clogged up in the radiator and it is preventing the hot water from heating up. To heat your radiator efficiently, the air must be released. If your radiator is experiencing a lot of warmth, it should be checked.

Mould and dampness around the house

Grubby mould or mould can be found on walls in rooms that aren’t used often. This could indicate that your radiators require attention.

Radiators rattling

Your radiators may make strange noises like gurgling, gurgling, or rattling if there is trapped air in the heating system. This could be due to many reasons but it could also be an indication that your radiator needs to be bled. To ensure that the problem doesn’t get worse, you should have your radiator checked.

So, here’s how to bleed a radiator?

You can bleed your radiators yourself by following our simple step by step guide to bleeding a radiator and should help get your central heating back up and running properly in no time. 

1. Turn your heating on and wait until the radiators reach the maximum temperature.
2. Once the radiators are hot, carefully feel each radiator checking for cold spots. Cold spots suggest there could be air trapped in the radiator, so you will need to bleed any radiators in which you find them in.
3. Before bleeding your radiators, you need to turn off your central heating and wait until your radiators have cooled completely.
4. To bleed your radiators, you will need a radiator key or a flat-blade screwdriver. If you don’t have a radiator key, you can find one in most DIY stores.
5. At the top of your radiator at one end, there will be a valve, locate this and position a cloth beneath the radiator valve to catch any water.
6. Insert your radiator key into the groove on the valve. Slowly, turn the key anti-clockwise to open your radiator’s valve. You should hear a hissing noise after a couple of seconds, this is the air escaping.
7. Once all the air has escaped, you may find that water starts to leak out before you turn the radiator key clockwise to close the valve. Be careful not to over-tighten the radiator valve, or you may cause damage to the valve.
8. After you have bled your radiators the final stage is to check the pressure of your boiler gauge. If the pressure is too low, the pressure will need rebalancing. If the pressure is normal, you can turn your heating on as normal and check that there still aren’t any cold areas in the radiators.

Checking your radiators to make sure they are working or need to be bled again

Here at Compare Boiler Quotes, recommend checking the radiators in your home every couple of months to ensure you are getting the most out of your heating.

There are countless positive improvements for your heating system such as increased energy efficiency due to your radiators working to their optimum level. Because of this, your home should be warmer quicker meaning that you can use less gas to stay warm.

We get many enquiries asking where radiator keys can be purchased from and we always say the best place to purchase these is Amazon. You can get a pair of radiator keys which enables you to bleed your radiators here: Draper 73965 Brass Radiator Keys (1 Pair)

If You Are Still Wondering How to Bleed A Radiator and you still have cold areas in your radiators please call us on 0808 156 7704 a member of our experienced team will be happy to help you.

If you would like to book a service for one of our experienced Gas Safe engineers to come and help, please fill in your details in the below form. If you think you need a new boiler system, we offer some unbeatable deals with our boilers on finance packages.

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