How Do I Replace a Radiator?

Replacing your radiators can be a great way of boosting your home’s energy efficiency, making it warmer in the winter and cheaper to run at the same time, but it’s a job hardly any of us want to take on. Radiators don’t get replaced as often as they should, and it’s not uncommon to find radiators from the 70s or 80s in older homes when really, they should be replaced every 15 years, but all that plumbing and heavy lifting is too daunting for most people. So how can you grab yourself a slice of those savings at a fraction of the price? Let’s take a look.

Why replace your radiator?

New materials and technology have made newer radiators quite dramatically more efficient than older ones, with a 2020 model up to 50% more efficient than a 2000 model for example. Also, as radiators age, they flake rusted metal into their workings that form a sludge which further reduces efficiency and can damage your system.

Where to start

One of the most important things to ascertain about the radiator you’re trying to replace is the kind of wall it’s mounted on. It will either be a hollow stud wall or a solid masonry wall and depending on its age it may have suffered damp or other damage which can cause the plaster to fall away when you move the radiator. As a result, it’s a good idea to make checks and repairs to the wall before you start work because you could cause more damage that adds time and effort to your job unless you make repairs first.

• Step one

Your first step should be to prepare the old radiator to be taken off the wall. To do this, you’ll first want to make sure your heating is turned off and the radiator is isolated from the rest of the system, or you’ll get very wet! You’ll need to close the valves at either end to do this, and depending on the type of valve you have your radiator can work one of three ways, manual valves can simply be turned clockwise until shut, thermostatic valves can just be turned to zero, while lockshield valves can be adjusted by removing the cover and turned with an adjustable spanner.

• Step two

As you begin the next step, remember to have plenty of cloth at hand and a bowl to catch the water for this next bit. Once the valves are shut you need to loosen the nuts that hold the valves to the radiator, which will allow the water to flow out once you have opened the bleed valve at the top of the radiator (this may be under the cap). Once the water is gone you can safely lift the radiator off the bracket that holds it to the wall but be careful that there isn’t any remaining water still left in the radiator, or it could leak all over the floor.

• Step three

The next step depends on what kind of new radiator you have. If you’re replacing like for like, and you can re-use the same radiator brackets, then you can leave these in the wall. It will also mean that you won’t have to change the layout of the pipes that connect to the radiator. However, if you’re replacing this radiator with one that’s bigger or smaller you’ll have to remove the brackets and re-arrange the pipes, which is something we recommend you get help from a plumber with. You get much more flexibility if you have a masonry wall because it’s strong enough to support a radiator at any point, whereas a plasterboard wall requires the radiator to be placed where the vertical studs are – limiting its size and position. Whether you’re just replacing the radiator or the brackets too, the next step is to fix your new radiator to the brackets on the wall.

• Step four

Once the radiator is safely attached to the brackets you’ll need to re-connect your pipes to the valves in order to allow water to flow. You can then unseal your valves by reversing the action you took to seal them before.

• Step five

Your radiator is now attached to the wall and connected to your heating system, but there’s still one last task to complete before you’re ready to turn your heating back on. New radiators come full of air, which can displace water within the system and create cold spots or even stop your radiator from heating entirely. In order to get rid of the air, you’ll need to bleed the radiator. Once again, you’ll need a bowl and some towels to help catch any loose water that may have been in the pipes from leaving out.

• Step six

You’ll have already used the bleed bolt earlier in order to remove loose water from your old radiator, and you’ll need to turn to it again to get rid of the loose air. Using a flat screwdriver or a key you can open the bleed bolt, which should result in a hissing sound as the air escapes from your radiator. This should slowly decrease until a few drops of water come out of the radiator, indicating that the air has been released and only water is left. As soon as this happens you need to close the bolt and stop the water.

Things to remember

It’s a tricky job drilling into a wall for something as heavy as a radiator, so it’s always a good idea to double-check there are no wires or pipes where you plan to drill, which could be messy or even dangerous. A stud detector can be used to find out what’s behind the plaster in your wall without having to check, and it can also be used as designed to help place your radiator if you have to move the brackets to accommodate a bigger model. You should also remember to use wall plugs where necessary to protect your stud wall or plasterwork from damage under pressure.