How to bleed your radiators

What you need

Radiator bleed key (may not be needed if your radiator has an adjustable nut, just use a small spanner/wrench)

Radiators that don’t work properly are a real pain, but it’s not too tricky to fix if you think it’s air in the system. Here’s how!

Step 1
Air gets in there when you add new water, and can also build up due to the water pump.  How do you know? The tops of radiators will often be cold, or the whole radiator.  Also high level pipes may not feel hot.

Turn of your central heating system.  There’s no need to shut the whole thing off, just make sure the thermostat is turned right down so it won’t turn and start water pumping around and potentially all over your floor.  It can get more air in too!

It works best with warm water in the system (the increased water pressure pushes the air out), simply turn the valve ANTI-CLOCKWISE until you hear a hissing, which is the air escaping.  You can use a cloth to catch any water that may spray out, careful, it could be hot!

Once Water starts to dribble out, tighten the nut/valve again (not too tight). Done! Try your heating, if the whole radiator now feels hot you’ve cracked it…