Bleeding radiators

[gloriaaa]

What is the proper way to bleed a radiator?

don't know if it's proper but i've always just turned the thingy at the end (with a key thing) and le the air out until water appears. seems to work.

Yep what Dora said. Use a cloth to protect your hand from steam and to catch any drips.

Do you have a key thing?

Get a bit of kitchen roll or old rag and hold it just under the bit where you turn the key. Turn it gently until you hear air hissing out. Meanwhile, check how far up the radiator has now got hot and how much is still cold. When the heat gets near the top and/or when you hear the hissing noise changing, you'll know the liquid is getting very near the top, so you then tighten off the key again.

No key as such. Do you mean the one bit that you can turn that is not the temp control? Does the heating need to be on when you are doing it?

No, you need to buy a radiator key. You can get them from B&Q or Wickes etc for about £2.
It's a brass key with a square-shaped hole at the end.
You put the key into the matching square-shaped bit at the top of your radiator, and turn it slowly until you hear air hissing out of the radiator. This is the air bleeding out of the radiator.
Yes, you need the heating on while you do it.

A plumber told me that the heating should be cold and off when doing it.