It only needs bleeding if it is hot at the bottom and cold at the top.Firstly turn your boiler OFF.Then get a cloth and your bleed key.At one end of your rad there will be a bleed valve which the key fits.Crack it loose but do not take it out,place the cloth close to the bleedvalve until you hear the air start to spit,then tighten it back up.Turn the boiler back on and you should find it heats to the top.
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