top of page
  • Writer's pictureCristie O'Leary

The simple way to bleed a radiator

If you're experiencing cold spots at the top of your radiator or your heating system isn't as effective as it should be, it could be that your radiators need bleeding. Bleeding a radiator is a simple process that can be done without the need for a professional. In this blog post, we'll guide you through the 8 simple steps of bleeding your radiators.

Before we get started, it's important to note that bleeding a radiator involves releasing any trapped air from the system. You'll need to be careful not to release too much water or cause any damage to your heating system.

Step 1: Identify which radiator needs bleeding

The first step is to identify which radiator needs bleeding. Turn on your heating system and wait for all the radiators to warm up. Once they're all warm, check each radiator for any cold spots at the top of each radiator. Any radiators which are cold at the top will need bleeding.

Step 2: Turn off your heating system

The next step is to bleed your radiator, make sure your heating system is turned off. This will allow the radiator to cool down and make it easier to work with.

Step 3: Prepare your tools

You'll need a few tools to bleed your radiator. These include a radiator key and a cloth or towel to catch any water that may be released. You can purchase a radiator key from most hardware stores or online.

Step 4: Locate the radiator valve

Once you've identified the radiator that needs bleeding, locate the radiator bleed valve. This will be located at the top of the radiator and is a small square or hexagonal shaped valve.

Step 5: Release the trapped air

Insert the radiator key into the valve and turn it anti-clockwise. You should hear a hissing sound as the trapped air is released. Hold the cloth or towel underneath the valve to catch any water that may be released. You will only need to open the bleed valve slightly to allow the air to be released. Be careful not to unscrew the bleed valve too much or it will come out of the radiator and you will be left with water pouring out.

Step 6: Tighten the valve

Once the hissing sound stops and water starts to come out, use the radiator key to tighten the valve up again. Be careful not to overtighten the valve as this can cause damage and will prevent you from being able to bleed the radiators again in the future.

Step 7: Check your heating system

Turn your heating system back on and wait for the radiator to warm up. Check for any cold spots at the top and repeat the process again if necessary.

Step 8: Check the pressure

Now you have bled your radiators you will need to check the pressure on your boiler / central heating system because bleeding the radiators may lower the pressure within the system. If required, top up the pressure using the filling loop.

Bleeding your radiators is a simple process that can be done without the need for a professional. However, if you're unsure or uncomfortable with bleeding your radiators, it's always best to call in a professional plumber. Stembridge Limited is your local plumbing and heating company based in Littlehampton, West Sussex. Our team of experienced plumbers and heating engineers are on hand to assist with any plumbing or heating issues you may have. Contact us today to book an appointment.

You can call us on 01903 389007 or email us at

At Stembridge Limited, we take pride in being a trusted plumbing and heating company serving Littlehampton and the surrounding areas. We have been providing high-quality services to our clients for many years, and we are dedicated to delivering exceptional workmanship every time. Whether you need a boiler repair, new boiler, central heating installation, or bathroom refurbishment, we have the skills and expertise to get the job done efficiently and effectively.

We understand that plumbing and heating issues can be stressful and disruptive, which is why we offer a trusted and reliable service in Littlehampton, Bognor Regis, Chichester and the surrounding areas to ensure that we can be there for you when you need us the most. We are fully equipped with the latest tools and technology, allowing us to diagnose and resolve issues quickly and with minimal disruption to your daily routine. Our commitment to customer satisfaction has earned us an excellent reputation, and we are proud to have many loyal customers who choose us time and time again.

At Stembridge Limited, we believe in providing a reliable and transparent service. We offer free, no-obligation estimates, and our prices are competitive and fair We are always happy to answer any questions you may have and will provide clear and honest advice to help you make informed decisions about your plumbing and heating needs. We are committed to providing an excellent customer experience from start to finish, and we guarantee all of our work for your peace of mind.

You can call us on 01903 389007 or email us at



Commenting has been turned off.
bottom of page