Skip to content
Right pointing chevron

Common radiator problems

My radiators are cold upstairs but hot downstairs

Cold radiators upstairs in your home is most likely to be caused by a blockage in the ball valve or there is a lack of water/low pressure in your expansion tank.

We advise seeking professional help from a qualified engineer in this situation to carry out the repair safely. It’s important to remember all heating systems should be regularly checked by a Gas Safe registered engineer.

My radiators are hot upstairs but cold downstairs

If you are experiencing problems with your downstairs radiators, there could be an issue with your central heating circulation pump. This can often happen when your heating has been switched off for a few months e.g. over the summer.

Indicators to look out for are:

  • Your pump is noisy and making a grating sound
  • The water flow pipe isn’t hot when heating is on
  • Plastic casing is hot
  • There is a leak coming from the pump
  • Loss of power
  • Speed settings are incorrect

These can be caused by something simple such as a blockage or trapped air which can be fixed. If not, the pump may be breaking down and be in need of replacement. Speak to a Gas Safe registered engineer for further assistance.

My radiators are cold at the top or in patches

If your radiator is cold at the top this could be caused by debris, trapped air or rust.

This issue is also easy to fix. Remove trapped air by bleeding your radiators. If this does not work, speak a qualified engineer to advise what action to take next.

The middle and/or bottom of my radiator is cold

If you are experiencing this issue, there may be a build-up of debris or sludge which is obstructing parts of the bottom of the radiator. Fixing this may need the radiator to be removed or the use of chemical additives.

We advise seeking professional help from a qualified engineer in this situation to carry out the repair safely. It’s important to remember all heating systems should be regularly checked by a Gas Safe registered engineer.

Liberty customer hub: common central heating problems