How to replace a broken radiator valve

How to replace a broken radiator valve

Fixing a broken radiator valve

Sometimes a radiator may not be working to its full capacity and that can be due to a broken or damaged radiator valve. If you already have some experience with DIY projects, replacing a radiator valve is something that you may be able to do yourself by following the steps below.

  1. Switch off your central heating
  2. Drain the heating system
  3. Remove the old valve
  4. Fit the new valve
  5. Refill your heating system

1. Switch off your central heating

Make sure your whole central heating system is turned off. You don't want to be dealing with any hot water water spilling our or your heating system trying to come on when their is no water in the system. Ensuring everything is off befor you start the job will simply make everything safer and easier.

2. Drain your heating system

After your heating system has been switched off and allowed to cool for around 30mins, you will need to drain the system of water. If you have a combi boiler you can follow the following steps.

  • You will be able to drain the water from the system by locating the drain cock and securely attaching a hose to it.
  • After ensuring that you have covered the floor in rags or towels to catch any leakage, you should close the valves.

If you have a conventional cylinder tank, it is best to seek professional help.

3. Remove the old valve

Securing the body of the valve with a wrench you can then unscrew the capnuts and remove the valve. Then unscrew the valve cap nut to remove the old valve. At this point, it's a good idea to take the opportunity to thoroughly clean the pipe with wire wool to remove any rust or grime.

4. Fit the new valve

Unscrew the valve adaptor from the radiator. Wind PTFE tape four or five times around the threads of the new adaptor and screw it into the end of the radiator.

You can then fit the new valve, but do not tighten the cap-nut just yet. Holding the valve body with a wrench, line it up with the adaptor and tighten the cap-nut. After this, you will be able to tighten the cap-nut that holds the valve to the water pipe.

5. Refill the system

Now that your broken radiator valve has been replaced you will need to refill the system before you can get it back up and running.

To refill the system find the filling loop beneath the boiler and turn the valve. Increase it until the pressure gauge reaches 1 ½. Follow our advice on how to bleed a radiator then once you have bled your radiators, turn the filling loop valve on the boiler again. Increase it until the pressure gauge reaches 1 1/2.

Remember not to carry out any work without being sure of what you will be doing. It can be dangerous and may end up causing greater problems with your central heating system. If you are in any doubt seek professional help.

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Radiator valves at Trade Radiators

Trade Radiators provide an unrivalled selection of Radiator Valves, from modern to traditional, copper to chrome, thermostatic to manual we should have a set to suit your requirements. All our valves come with extensive guarantees and free 24hr delivery.

You will find everything from valves, hangers and hooks here and you can always get advice on certain maintenance aspects from our blog. Here at Trade Radiators we try to make sure you can get everything you will need from us and help you save money in the process. High quality radiator accessories suitable for use with selected ranges.

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