My radiators are cold or aren't working properly

If it’s just one, or a few aren’t working but not all of them there could be couple of things to try first.

The radiator is cold at the top

It’s likely you will just need to bleed your radiator. We don’t come out to do this for you. It’s simple and easy to do yourself - here’s a video you can watch to show you how to bleed your radiator.

Something important to remember before you do this is that if you have a combi boiler, bleeding a radiator can cause your pressure to drop on your boiler. You may also need to re-pressurise your boiler after you bleed a radiator. Here's our video on how to repressurise your boiler. 

To bleed the radiator, you will need a radiator bleed key or screwdriver, and something to put under the radiator to catch the water like an old cloth or kitchen roll.

If the heating has been on and the radiators are hot, you need to let them cool down before bleeding, so the water isn’t hot when it comes out and to let the system pressure settle down.

Turn the bleed valve at the top of the radiator slowly until you can hear air coming out. Do not take it all the way out. If it comes all the way out, you won't be able to shut it off when the water appears.

When water starts to come out of the valve, turn it off.

Some older style radiators have their bleed point on the back of the panel. These can still be bled in the same way by using a radiator bleed key.

The radiator is completely cold or cold at the bottom

First, turn the thermostatic radiator valve to maximum.

There are two valves on your radiator, one on either side. Check that both valves are fully open. This can be done by opening the thermostatic radiator valve (if fitted) to its highest setting. The valve on the other side of the radiator is known as a lock shield valve. Some radiators have this type of valve at both ends, and you might need to take the plastic top taking off so you can check it's open. You may need a pair of pliers or a small spanner to turn this fully anti-clockwise. If this works and your radiator gets warm, then there’s no need to report a repair.

Watch our video on how to open and close your lock shield. 

If this doesn’t work, then unscrew the top part (the plastic bit) of the thermostatic valve anticlockwise, which should remove the top. Sometimes this part of the valve breaks inside and by removing it the radiator may then work.

It is also possible that the pin inside the brass part of the valve has stuck down in the off position. This will sometimes pop up when the plastic top is removed. The top part of the thermostatic valve is not connected to the water side of the valve, so don’t worry - you won’t get wet by removing it. You shouldn’t need to touch the brass part of the valve.

One of the radiators is still cold

Turn all the other radiators off using the TRV and leave the affected one on the maximum setting. This will force the heating to flow through this radiator. Ensure that the lock shield valve is also open fully before trying this.

If the radiator now gets hot, it's likely that the problem was an airlock, and you will have now sorted the problem and you can turn your other radiators back on.

If this doesn't work, or you keep having problems like this with your radiators, then report a repair to us.

How do I report a repair?

You can report a repair to us at anytime, anywhere using My Account or contact us via Live Chat. Let us know when reporting that you’ve followed the advice and what you’ve tried to get it working, this helps us to assess what to do next to get the right person for the job.