Finding a puddle of water underneath your radiator is a clear signal that you have a leaking radiator. Before you do anything, you should place an absorbent material such as a towel in the area where the radiator is leaking water to prevent any water damage. A radiator leaking water can be caused by multiple components of the radiator, which include:

  • Radiator Valve
  • Spindle
  • Gland
  • Corrosion build up
  • Pipe joint

Leaking Radiator Valve

If your radiator is leaking water from the valve, you will need to firstly drain the valve and then turn off both the supply valve and lock shield valve. These will both drip water, so make sure you have a bucket nearby to catch the water. You will then want to use an adjustable spanner to remove the union nut and open the bleed valve to allow the rest of the water to drip from the radiator.

You will then need to wrap the valve tip with a suitable PFTE tape and retighten the union nut and open the valves. Once the water have been restored, you can check for any new leaks and close the bleed valve.

Our team of heating engineers in Cardiff perform this type of servicing on a regular basis and using the PFTE tape is a fix of many leaking radiator valves.

leaking radiator valve

Radiator Spindle Leaking

The spindle of a radiator is the connection between the pipework and the radiator itself and will leak when damaged. Luckily, it is one of the easiest fixes when it comes to a leaking radiator and with some PFTE tape wrapped around the spindle, you can stop the leak fairly easily.

Water Leaking From Valve Gland Nut

The gland nut can become loose overtime and leaking primarily because of this. Simply tightening this gland nut can solve the issue of water leaking from the radiator. If this doesn’t fix the issue, you can look into replacing the olive inside of the coupling but this will require draining of the heating system.

Corrosion on the Radiator

The mixture of age, water and metal is a recipe for corrosion build up that can cause a build up of sludge inside of your radiator. This sludge will cause corrosion inside and outside of the radiator, which can cause big issues. Below is an example of corrosion that has built up on the valve:

rust on radaitor

If you notice corrosion on the outside of the radiator, it is more than likely that it will be present inside the radiator too. This can cause “pinhole” leaks, which means the radiator is pretty much at the end of its life and will need to be replaced. If you need a Cardiff plumber to confirm that this is the case, you can send in a photo or request a call out before scraping all your radiators.

Radiator Joint Leaking

The join between the pipes and radiators are prone to leaking but can often be repaired by simply tightening the valve with a spanner. However, if that does not fix the leaking radiator, you may need to drain the system and wrap PTFE tape around joint and ensure the valve is tight.