Solving common radiator problems

Here we highlight some common radiator problems and look at what you can do to fix them.

Your radiator is cold at the top but warm at the bottom

Your radiator probably has air trapped inside. You can let the air out by bleeding the radiator with a radiator key. You can buy this from a DIY store.

If you're not sure how to do this you can watch our short video on bleeding a radiator, which will show you how.

Your radiator is warm at the top but cold at the bottom

You might have sludge or rust blocking your radiator or pipes.

This is tricky to fix. So it's best to ask a Gas Safe registered engineer to take a look. They may need to flush your central heating system to clear the blockage. After that, they may add an inhibitor solution to prevent future build-up.

Your radiator is cold all over

If your heating is on and other radiators are working fine, you may have stuck or frozen valves that are stopping water getting into the radiator. Or, again, sludge or rust may be to blame.

In some cases, there may be a bigger problem going back to your boiler. We recommend you ask a Gas Safe registered engineer to take a look and fix it.

Your radiator is making strange noises

Radiator noises aren't usually anything to worry about. A ticking or clicking sound is just the metal of the radiator expanding or contracting as it heats up or cools down.

If the noise is coming from under the floor, it's probably due to the pipes expanding or contracting.

You might also hear whistling if the water flow rate is too high. Try turning the radiator valve fully on. This should stop the whistling.