How To Fix A Radiator Leak

Introduction

Most radiator leaks aren't serious, but they can stain your carpets, cause your radiators to rust and affect your heating system's efficiency if they are left unattended. To fix any leaks, you will first need to identify where they are coming from. Below, we've listed some of the most common reasons why radiators leak and talk you through how to fix each one in just a few simple steps.

Identify Where The Leak Is Coming From

Radiator leaks can come from a number of different places, so you'll need to figure this out before you can begin any repair work. To do this, dry your radiator completely using a towel and place some tissue roll over each fixture. If one part of the radiator soaks the tissue roll, you've found the source of your leak.

Body (corrosion)

Sediment and minerals from unfiltered water will build up over time if they are left untreated. This will lead to corrosion inside your radiator, causing water to leak from the body (or the affected area).

Valves

If you find that your radiator valve is leaking, this is likely due to damage in the internal spindle packing. However, leaks will only occur when the valve is open and stop when it is closed. Valve leaks are relatively common and are easy to fix.

Spindles

The spindle connects your radiator to the pipework and is often the main cause of a leak if it becomes damaged or loose.

Glands

A radiator gland is a small fixture that lives underneath the plastic lid of the valve. If you fix your valve and it's still leaking, the issue may be the gland.

Pipe joints

If you have a compression heating system, you will have a series of joints connecting your radiator to the pipes. If these become loose, leaks will occur.

Each of these parts will require a slightly different method to fix, so read the instructions listed below carefully.

What do you need to fix a radiator leak?

A spanner, a flat-head screwdriver, PTFE tape, towels and bowls.

How To Repair...

How To Repair A Leaking Valve

To repair a leaking valve, you will have to drain the system to below where the leak is coming from. Once you've done this, turn off the lockshield valve (which has the plastic cap) and the supply valve (where water enters). Remember to count how many turns you make to close the lockshield valve completely.

Next, place towels and bowls underneath the radiator and undo the union nut. Once you've done this, turn the bleed valve to release any water and wrap the tip of the valve in tape (preferably PTFE). Now, re-tighten the union nut and open the lockshield and bleed valves. Once your radiator has filled up again, check to make sure there are no leaks. If you're certain the issue has been fixed, close the bleed valve.

How To Repair A Spindle

A simple problem to repair, all you need here is a spanner to tighten the gland nut. However, if the leaking doesn't stop after you've tightened this, undo the gland nut again and wrap some PTFE tape around the spindle.

If this fails as well, you may have confused a spindle leak with a valve leak, so follow the instructions we have listed above. Alternatively, call a plumber and see if they can offer further guidance.

How To Repair A Gland

If you have followed our instructions on how to fix a valve but your radiator is still leaking, the issue might actually be with the gland. However, this is a simple fix if you have some PTFE tape.

First, turn on the valve and see if any water leaks from underneath the cap. If it does, turn off the lockshield valve as well. After removing the cap, unscrew the gland nut and wrap a 20cm piece of tape around the spindle. Using a flat-head screwdriver, force the tape into the body of the valve before screwing the gland nut back on. Finally, replace the cap and switch on the valve.

How To Repair A Pipe Joint

Most modern central heating systems use compression valves to join pipes to radiators. If one of these starts to leak, the valve can be tightened with a spanner.

However, if the leak doesn't stop, drain the system to below the source of your leak and undo the nut at the joint of the leaking pipe. Next, pull the pipe free and wrap some PTFE tape around it. Finally, re-tighten the nut.

Can Leaks Be Fixed If They're Caused By Corrosion?

Unfortunately, if your radiator is leaking from its body as a result of corrosion, you will need to replace your entire radiator. In the meantime, there is a temporary fix you can do.

It's possible to add a plastic resin sealant to a feed and expansion tank to stem the water flow. However, you can't use sealant in a sealed central heating system.

Is The Valve Still Leaking?

If your radiator valve is still leaking after you've followed the different methods above, you will probably need to replace it. Before you replace a radiator valve, make sure you purchase the same one. You will then need to:

1. Drain all water from your heating system.
2. Unscrew any nuts that connect the water pipe to the valve using a spanner. You will also need to completely unscrew and remove the old valve.
3. Gently clean the valve threads and wind them with your new valve.
4. Screw this into the radiator and refill your heating system. Note: you may need to bleed the radiator to remove any trapped air.

If you're unsure which radiator valve you need, contact the experts at Just Radiators today. We stock a range of different valves, including angled, corner, manual, square and straight options.

Find Your Perfect Radiators With Just Radiators

As touched on briefly above, there are many materials and finishes to choose from when picking out the perfect radiator. Traditional radiators, which are made of ceramic, remain a popular choice for many households, but other types such as steel are fast becoming the go-to.

You can also choose from other materials and finishes such as cast iron, wooden, aluminium, and chrome. Overall, it just requires a bit of browsing online to find the perfect radiator for your space. There's plenty to choose from!

Again, it depends on the overall style and tone of your space; ceramic heaters are quite bulky, for instance, and so are perhaps not suitable for your space otherwise contemporary and sleek, and vice versa with steel, minimal radiators.

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