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How To Fix A Leaking Radiator

by | 29 Dec 20 | Help and Advice | 0 comments

How To Fix A Leaking Radiator

How to fix a leaking radiator? When your radiator in your home has water leaking from it, this can be a frightening experience and occurs more often than we think.


What Causes A Radiator To Leak


Believe it or not, there are numerous reasons that could cause your radiator to leak. Two of the most common cause is a loose or damaged spindle or your radiator has rust and corrosion.

Different Types of Radiators



Most of us would agree that a radiator is essential in our homes.  The amount of styles and types of radiators are numerous, however, the most commonly used ones are the white ones.  Broken down further, this can be either single panel or double panel radiator.

Photo showing a single panel radiator with a pair of black gloves on it.
Photo showing a double convector radiator.

Areas Where A Radiator Can Leak


One of the most noticeable sign that your radiator is leaking is you will see water on the floor.  You will notice this near the radiator or if you have carpet because that area may be wet.  A radiator can also leak from either the valve or from the actual radiator itself.  



Rusted or Corroded Radiator


Radiators overtime can become corroded, which is commonly caused by your central heating system having sludge in it.  Sludge?  Exactly what is this?  For all of us who are not that technical, this is a black mud like substance.  Yucky right!  Wondering to yourself, how did that get in the heating system?  

Leaky radiators happen due to various reasons, however one main cause is that the radiator is corroded.  Corrosion can be caused when no chemical was added if you have had the heating system drained down. 

Yes, I know I am getting more technical but let me explain. If you have had  a new boiler installed;  you had any of your radiators changed or your boiler needed to be repaired or replaced.  A competent gas engineer will put back chemicals such as a rust and corrosion inhibitor into your heating system.  

Although this does not stop the rust, it helps to slow down the process.  See told you I would explain it to you.  There is also another way that would help slow down your system from getting rust or corrosion.   

Ready for it, this is by installing a magnetic filter which is installed on your cold water pipe usually beside the boiler.  Now you are asking yourself, what is a magnetic filter?

Magnetic Filter


As the name suggest, it acts as a magnet on your heating system and helps to remove any debris that may be going through your pipework.  Is it necessary to have one fitted?  Some may think not but to help to filter the water going into the boiler, the answer plain and simple is, yes.  Stop cutting corners because in the long run you are going to wish you had installed one. 

 Anyone will do the job just fine and your gas engineer will recommend one.

Photo showing a magnetic filter that is attached to a pipe for your boiler.
Photo showing radiator spindle.

Damaged Spindle


I know, I know, I deviated there a minute, but wanted you to get the full picture before we moved on.  Where were we, yes, the other reason your radiator can leak.  Spindle is a joint that connects the main body of the radiator to the radiator valve.

Since we have now identified the possible causes of a radiator leak, the next thing is how do you fix it.  Hold on, don’t be so impatient, I was just getting to the part of how you go about repairing your leaking radiator valve.



First Things First


Turn off the water to your property.  Let us first locate your stop cock and then turning it off or if your radiator has an isolation valve, you can turn off from there.  For your convenience, we have a blog that instructs you on how to turn off an isolation valve.  


Yeah, you have now managed to turn off the water, let’s get to work.

Carrying Out The Repairs


Damaged Spindle

After investigation, if the spindle is loose, you can tighten the joint.  However, if after tightening, water is still leaking, then you would need to wrap some PTFE tape around the spindle then try tightening it up again.


Rusted or Corroded Radiator

Should the leak be caused due to a rusted or corroded radiator then there is no way around this I’m afraid and you will just have to replace the entire radiator.  Before you go whipping out your tools and get going.

In the United Kingdom, as an unqualified gas engineer, you must not do any work relating to your boiler. What do you mean boiler?  But it is my radiator that is leaking.  Unfortunately this is now where you are going to have to spend some money and obtain the services of a qualified and competent gas engineer.



What is Involved in Replacing Your Radiator

Previously stated above if your radiator is leaking due to rust or corrosion, the gas engineer if doing their job properly will do the following:

  1. Turn off the water just like what you did before you tighten the spindle.
  2. Drain down the heating system, which will remove all the water.
  3. Remove the radiator from the wall.
  4. Cap off the pipework for the radiator.

A new appointment will be made by the gas engineer to return to your property in order to come back and install the new radiator. During this visit, the cap will then be removed and the gas engineer will commence the process of installing your new radiator.