How to fix a radiator that is not working

How to fix a radiator that is not working

This How-To tutorial is aimed at fixing a single radiator that is not heating up. If more than one radiator is not working it could suggest something more serious.

Millions of homeowners in the UK and other countries rely on radiators to heat their homes. When something goes wrong with your radiator, however, it’s important to know how to fix it correctly, as an incorrect fix can cause leaks in your house and cost you more money. Multiple failing radiators could point to a deeper problem, but if only a single radiator is malfunctioning, you can repair it easily in a few simple steps. The problem can originate from three possible areas, each one of which we will go into detail, as well as their solutions.

The first thing to check for is to see whether the lockshield is open. The radiator’s lockshield is located on the side of the radiator towards the bottom and has a plastic cap to help prevent it from being changed. Start by removing the plastic cap, which will reveal the lockshield valve – a half-moon shaped brass spindle that should look something like the picture below.

How to fix a radiator

Using an adjustable spanner, turn the valve anticlockwise, which will open the valve and allow more hot water to flow into the radiator. After a few seconds you should be able to feel the pipes leading to the radiator warming up. If it remains cold, the issue lies elsewhere.

The next thing to try is bleeding your radiator. If your radiator feels warm at the bottom and cold at the top, there is most likely air trapped inside, which can obstruct the normal flow of water. (Note: It is strongly recommended to turn off the boiler and pump before proceeding). Look for the bleeder valve, which will be located at the top of the radiator on one side. Hold a cloth under the valve and use a radiator key to loosen the valve by turning it slowly anticlockwise. Any trapped air will start to come out, and you may hear a faint hiss. Let it run for at least a few seconds. Close the valve again when water starts to come out, as this means that all the air is gone.

How to fix a radiator

If you’ve tried the two methods outlined above and you’re still not getting heat, you may need to take a look at the radiator’s TRV (thermostatic radiator valve). This is the radiator’s control head and will be located near the bottom, on the opposite side of the lockshield valve. First, make sure it is fully turned on, on the maximum setting. Next, remove the TRV head.

The way this is done depends on the manufacturer; some feature a screw-on collar, while others, such as Danfoss, use lugs that can be popped off with a screwdriver. Removing this cover will reveal a pin or head that, normally, can be pushed down. With a cold radiator, however, this piece will likely be stuck down. The goal is to use force to get the pin unstuck. But be gentle! If manual coercion doesn’t work, use a set of long-nose pliers to wiggle the head upwards and loosen it up.

Note: If you find that the pin gets stuck again when you push it back down, you’re better off buying a replacement TRV.

How to fix a radiator

By now, your radiator should be back in full working order. Keep in mind that the outlined solutions were intended to fix single broken radiators. If you have two or three or more radiators in a line that aren’t working, it’s possible that the system is unbalanced. Balancing a system is outside the scope of this article, but this DIY guide should help you get off to a good start in troubleshooting your system.

Screenshots and content courtesy of https://youtu.be/wqku_Rc_YuI