DuraTherm Vertical Double Flat Panel Designer Radiator - 1800 x 532mm

How to Fit & Replace a Radiator

When it comes to keeping our homes toasty and warm, radiators are one of the most reliable ways of heating our properties. But like all fixtures in our homes, these warming necessities can sometimes need replacing, either for improvements in efficiency or due to wear and tear.

Removing and replacing radiators that aren’t working correctly can be an excellent way to save energy, ensuring that your central heating is working to the best of its ability (because let's face it, nobody wants to be cold!) Efficiency is a must when it comes to heating our homes, not just for your own comfort, but also for your bank account!

Although wear and tear with a radiator is unavoidable, when it comes to getting stuck in and fitting a new one, how do you actually change it?! Radiators in particular can last for years with proper maintenance but what do you do when it needs replacing? How do you fit a radiator? That's where Plumbworld can help! In this blog, we will guide you on why you may need to change a radiator, how to remove it, and (perhaps most importantly), how to fit a replacement yourself!

Read on to find out how to remove and replace a radiator…

Should I Replace my Radiator?

Park Lane Traditional Colosseum Triple Bar Column Radiator Anthracite 600 x 1190mm

Replacing your radiator can depend on a variety of factors, but some of the common reasons we believe you might want to trade your radiator for a new one are as follows: the quality of your installation, the unit itself, and the upkeep of the radiator, including its age.

If you are beginning to notice uneven heat distribution or a total absence of heat altogether, then it might be time to say goodbye to your beloved radiator and find a replacement. Although certain radiators can last for decades, their efficiency may start to decline over time (much like everything else!). That's when we would advise you to start looking to replace your radiators.

Some of the main reasons for replacing a radiator include:

  • Rust, corrosion, and blockages for the radiator that can no longer be fixed
  • The radiator is no longer efficient compared to the current market
  • Needs to comply with quality and safety regulations
  • New home - meaning you may want new fixtures
  • Improve the visuals of your radiators to match a new room design
  • Improvements in efficiency (both with heat and water)

Calculating BTU

To ensure your heating is as efficient as possible we advise calculating the BTU (British Thermal Units) needs of your home before purchasing a new radiator.

Calculating your home's heating requirements has never been easier with our simple heating calculator.

Read more: Heating Advice: How to Check Your Radiators

What Equipment will I need to Change my Radiator?

Tools for changing a radiator

Like all DIY projects, you'll need some handy tools at the ready for when you tackle replacing a radiator. Some of the kits you’ll need when it comes to removing and replacing your radiator include:

  • Spirit level
  • Radiator key
  • Pipe cutter
  • Adjustable pipe wrench
  • 2x Adjustable spanners
  • Tape measure
  • Bucket
  • Dust sheet
  • Pipe tape
  • Screwdriver
  • Drip tray

Read more: A Guide to Bathroom Heating

How to Change a Radiator

Measuring a new radiator

Replacing a radiator is usually reserved for a competent DIY expert who is confident and able to handle plumbing tasks. However, if you're a novice DIY-er who wants to get stuck in and accept a new challenge, keep on reading! We will aim to guide you through the process to make it look as seamless as possible.

Before you get started, it will help to check the walls where your radiator usually sits or stands against. Are there any cracks or crumbling plaster? If there are, you may need to make repairs before you fit your new radiator.

Top tip: If the wall is solid masonry, you’ll have a wider choice of replacement radiators to choose from than if it’s plasterboard!

How to Remove a Radiator - Step by Step

Step One: Turn off the water supply

water droplet

First things first, as with all plumbing jobs, be sure to turn off the water supply and central heating system in your home before you begin. Once this is completed, allow the water in the system to cool down before moving on to closing off the radiator valves.

At either end of the radiator, you’ll need to close and turn off the valves. One is the manual control valve that turns the heat on and off. Turn this off by rotating it clockwise until it can no longer turn. At the other end is the lockshield valve which controls the flow through the system. Take off the protective cap and turn the square top piece clockwise with a spanner.

Top Tip: be sure to count the number of turns needed to close your valves, as the valve should be opened by the same amount when you replace the radiator later on.

Step Two: Drain the old radiator

Your radiator has been isolated, now, you'll need to drain it. To do this, place a bowl, tray, or bucket under the manual control valve. Grip the valve with an adjustable spanner and hold it steady while you use another to loosen the nut on the valve (the air bleed valve) that is connected to the radiator.

Next, use a radiator key on the top edge of the radiator to slowly vent any trapped air out of the radiator.

Use an old rag, cloth, or towel to catch any drips from the valve and stop them from falling on your flooring. Continue draining the water from the radiator until the flow of water stops. If you start to notice your bowl/tray/bucket is filling up too fast, be sure to close the top valve, giving you time to quickly empty and replace. Once this step is complete, be sure to move over to the other side and repeat.

Step Three: Remove the radiator

DuraTherm Horizontal Double Flat Panel Designer Radiator - 600 x 1216mm White

Once the radiator is drained, you can then loosen and undo the nut that connects the lockshield valve to the adaptor in the radiator. For this, you may have to push the central heating pipes and valves outwards to free the radiator connections. After this, lift the radiator up to remove it from the wall brackets. We suggest getting some help with this bit, as it can be tricky!

There may be some water left in the bottom of the radiator, so tilt it and drain it into your bucket. The water may be dirty, so place the radiator on old towels or sheets.

How to Fit a Radiator - Step by Step

K Rad Kompact Type 22 Double Panel Plus Radiator 600 x 1500mm

Now you've managed to successfully remove your old radiator, it's time to tackle the next part - installing your new one! Make sure you have everything ready for when you embark on this next step in the process.

It’s likely that your existing brackets won’t be compatible with the new radiator, so you’ll need to unscrew them. Therefore, you may have to fill any gaps left from the previous fixing holes.

Top Tip: Try attaching reflective radiator tape to the wall behind where the replacement radiator will hang. This will bounce heat back into your room and can help lower your heating bills!

Step One: Drill for new brackets

Before drilling into the wall, you’ll need to make sure you’ve checked what’s behind it with a digital detector. These handy devices will let you know whether there are any pipes, cables, or studs where you’re planning to drill. Run it over the surface and it’ll tell you if there are any hazards. Once this is complete, you can begin drilling where you'll need to fit your new brackets.

Step Two: Fit the new brackets

Once you’ve finished drilling, fit the brackets to the wall and you will be able to fix your radiator to the brackets. You can do so by following any manufacturer's instructions you have received with your brand-new radiator.

Step Three: Tape and install your valves

DuraTherm Standard Anthracite Cross Head Angled Radiator Valves - 15mm

Get some PTFE or plumbing tape and wrap a 20cm length around each valve thread. So it’s easier to make adjustments, it's best to install your valves before attaching your radiator to the wall. Once this step is complete, open both valves fully to allow the radiator to fill with water from the central heating system.

Step Four: Lift and hang the radiator

Lift the new radiator up onto the wall brackets. Check the radiator is hanging straight and then you can tighten the fixings. This is a two-person job, so we recommend finding a DIY friend to help aid in this step, saving any unwanted damage to your new radiator (or you!). It’s much easier and less stressful if you have someone to help you.

Step Five: Open the valves and allow water in

White manual radiator valve

Make sure the manual control and bleed valves are fully open and open the bleed valve to allow water into the radiator. Once the radiator has stopped making an odd ‘gurgling’ sound and is full, open the lockshield valve by the same amount of turns as you needed to close it earlier.

Step Six: Final checks

Check all the joints and sealings are dry and waterproof. Make sure to tighten if necessary, and then once that's all sorted, you can turn your central heating system back on. Finally, perform some last checks to ensure no water is leaking out and that the radiator is getting hot evenly.

Step Seven: Relax!

It's now time to enjoy the fruits of your labour. So, sit back, relax, and snuggle up to your newly installed, warming radiator.

If you would like more heating inspiration and advice, take a look at the following posts - How to Check and Maintain Radiators - Designer Radiator Buying Guide. What's more, if all this talk of refitting radiators has made you want to buy a brand new one, discover our range on Plumbworld.


We love seeing your bathroom and kitchen makeovers and sharing them on our Instagram page - if you've had a Plumbworld renovation, tag us in your photos to be featured!

We would love to see, so why not share your favourite designs on social media with us?

Find us at:

Facebook | Twitter | Instagram | TikTok | Pinterest

Alternatively, sign-up to our newsletter for the latest offers, newest product launches and advice.

Are you planning a new bathroom or kitchen makeover? Shop online with Plumbworld for guaranteed lowest prices and next day delivery options.

Don’t forget to check out the rest of our blog for more bathroom and kitchen advice.


Share