Installation & Maintenance

Last Updated: Sunday, 11th February 2024

How To Install a Radiator Valve

When it comes to installing a radiator, you're going to need to also install a radiator valve. However, changing radiator valves on existing radiators is a task that can greatly improve the efficiency and functionality of your heating system.

Whether you have a leaking radiator valve, your radiator valve is stuck or you're simply looking to fit a thermostatic radiator valve to benefit from efficiency improvements, this step-by-step guide will walk you through the process of changing a radiator valve, ensuring that your home stays cosy and energy-efficient.

Anatomy of a Radiator Valve

Let's get started by understanding the components of a Thermostatic Radiator Valve. If you have a Manual Radiator Valve, don't worry, all the essential parts are the same. The only difference will be that you won't have the "Thermostatic Head".

Diagram showing the anatomy of a thermostatic radiator valve

The bits that you are going to want to take note of are the:

  • Securing Ring

  • Radiator Tail

  • Radiator Tail Nut

  • Compression Connection

These are all of the parts that usually need assembling.

Things You Will Need

Supplies You Will Need

  • Plenty of towels or rags
  • Two/Four large buckets
  • Waterproof/Plastic sheet (if you have carpets)

Tools You Will Need

  • PTFE Tape
  • Pipe Cutter
  • Pliers
  • Adjustable Wrench
  • Jubilee Clip
  • Small length of hose
  • Flat head screwdriver


  1. Turn Off the Heating System

    Start by turning off your heating system. This is crucial to avoid hot water or steam flowing through the radiator while you're working on it, preventing any accidents or burns. If you've recently had it on, wait for it to cool down. Check if the radiator, and the pipework around it, that you're about to work on is cold.

  2. Gather Your Tools and Materials

    Make sure you have all the tools and materials listed above within arm's reach before you begin.

  3. Drain the Radiator

    Cover as much of the floor beneath the radiator as possible with your waterproof sheet (if you need it) and towels to catch any spills. If you can isolate your radiator, then do this now. Locate your isolating valves and using your hands or your flathead screwdriver, close the valves. If you don't have this option, unfortunately, you are going to have to drain your entire system. Find the lowest drain-off valve and follow the next paragraph. If you have a drain-off valve for your radiator, then attach your length of hose to the drain valve and secure it with the Jubilee Clip. Point the hose into your bucket and carefully open the valve to drain the radiator. When there is no more water draining out, close the valve and come back to your radiator. The final step is to place a bucket underneath each of the radiator valves you want to remove. Keep other buckets very close by, ready to replace when they fill up. If you've been able to do all of the above, then that's great. If not, then make sure your buckets are secure and ready. You're about to have a much messier experience. Now follow the next step.

  4. Loosen the Radiator Tail Nut

    Making sure you have buckets under your radiator valve to catch any remaining water, turn the Radiator Tail Nut anticlockwise to loosen the connection. If there is water draining out, then let this happen. Don't move to the next step until there is no significant flow.

  5. Completely disconnect the Radiator Valve

    Continue turning this nut anticlockwise to disconnect the Valve from the radiator. Then follow suit with the Compression Connection.

  6. Prepare the New Valve

    Wrap the threads of the new valve with PTFE tape to ensure a watertight seal. Make sure to wrap the tape in the direction of the threads to prevent unravelling. More is better here. You need to make a good seal.

  7. Attach the New Valve

    Put the Radiator Tail inside the new Radiator Tail Nut and carefully screw the Radiator Tail into the radiator threaded connection. Use an adjustable wrench to tighten the screw, ensuring a snug fit. Be cautious not to over-tighten, as this could damage the threads. Then screw the Radiator Tail Nut onto the valve to complete the connection. Again, you can tighten this for a snug fit, but don't over-tighten.

It may seem like a daunting task, but with the right tools and a clear understanding of the steps involved, it is a very manageable DIY job. By following this step-by-step guide, you can ensure that your home heating system remains efficient, reliable, and comfortable, all while potentially reducing your energy consumption and bills. If you're unsure about any step or encounter unexpected challenges, you can always call in a professional plumber to help.

Any more questions?

If you have any queries or questions about the products we sell, or even your next project, give us a shout! We'll try our best to give you a hand.