Sometimes a radiator may not be working to its full capacity and that can be due to a 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.
You will need to drain the system to begin with. Those of you with a conventional cylinder tank will need professional help. For anyone with 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.
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. You will also have the opportunity to thoroughly clean the pipe with wire wool here.
Next, 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 however do not tighten the cap-nut 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.
Now that your damaged 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.