Central heating systems are designed to keep our homes warm, but they don’t always work as effectively as they could do. If your radiators are not heating up properly, it probably means that the system needs bleeding. The process of bleeding central heating pump should be done regularly and is fairly simple...

Why Radiators Need Bleeding
As water enters your central heating system, some air will also get in. This will also build up through the motion of the impeller in central heating pumps. The air moves upwards in water, preventing the top of radiators from heating up. If the bottom is definitely warmer than the top, your radiators or central heating system need bleeding.

Bleeding Radiators
Central heating pumps should be turned off before bleeding radiators; otherwise you could put more air into the system and make the issue worse. If you have a sealed system, the pressure will be reduced by bleeding, and you will have to re-pressurise it afterwards. If you don’t know how to do this, you should speak to a heating engineer first.

When there’s warm water within the system, turn off the pump. The bleed valve is usually located on top of the radiator. Fit the bleed key on to the valve, and wrap some cloth round to soak up any water. Move the valve anti-clockwise half a turn, and you should hear air hissing out. When water begins to come out, turn it clockwise half a turn. Check the pressure in a sealed system and re-pressurise if necessary.

Bleeding a Circulation System
You will find the bleed valve usually in the loft. There again needs to be warm water in the system before you turn off the pump. You won’t need a bleed key, as they are generally fitted with a knurled release. Open the valve using a piece of cloth to catch any water that dribbles out. Once this occurs, close the valve again. Re-pressurise sealed systems if required.

Other Problems
If the radiators are still not getting hot after bleeding, there might be another problem source. If the radiator hasn’t worked after being refitted or installed, ensure the shield valve hasn’t been closed too far down and that, if fitted, the thermostat valve is on the radiator’s inlet and not the outlet.

If the radiator has been working before but now isn’t, check for air locks in the pipes or if there is a blockage in the outlet or inlet.

If this doesn’t work or you require new components for your heating system, at Anchor Pumps we stock a range of central heating pumps and accessories that are suitable for different systems.