The Self Build Self Help Site Replacing a Radiator
Replacing a Radiator
Sub header photo of radiator

Replacing a radiator can be done quite easily with a little basic knowledge of plumbing and should take only a few hours to do. However, if youíre not completely confident itís best to hire a professional.

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You will need a radiator key, pipe wrenches, adjustable spanner, bucket, cloth and pipe tape.

1. Turn off the water supply and boiler

Firstly you must turn off the heating and water and allow the radiator to cool so the water inside isnít too hot when you come to drain it.

Once you have done this you can now turn the manual control valve handle clockwise to turn the heating off. If you have a thermostat valve this needs to be turned off and not just on the frost setting.

At the other end of the radiator there is the lock shield valve which controls the flow through system, next remove the plastic cap and with an adjustable spanner, turn it clockwise to close the valve.

It is important to remember how many turns it took to close it as this will be the same number of turns to open the new radiator. This is important to ensure the system stays balanced enabling it to distribute heat evenly throughout your home.

2. Bleed the old radiator

Now you need to bleed the radiator of air. This is done by locating the bleed valve which will be found on the top of your radiator. Using a radiator key open it and release the air. You will hear a hissing sound when all the water is released. At this point you need to tighten the bleed valve as all the air is out, you may also need a cloth to catch any drips.

3. Remove the radiator

Use a wench to grip the valve assembly ensuring it cannot be pulled loose from the pipe that is feeding it. Undo the nut holding the radiator to the valve at the other end in the same way. Then open the bleed valve at the top of the radiator undoing the nut completely so that air can enter and encourage the water out quickly. Be ready with a bucket under the valve.