Why won’t my radiator work? Everything you need to know this winter

However, after months of warm weather, many may come to realise that their radiators are not working as they should.

This can be because of a number of reasons with blockages and air pockets causing issues for these units.

Why is my radiator not heating up? All to know

Your radiator may have a leak (Image: Getty Images) Here are some of the reasons why your radiator may not be heating up, according to the experts over at Skills Training Group.

Air pockets in the radiator

If you’re noticing that your radiator is cold at the top and somewhat warm at the bottom, there may be air pockets in the system.

This sees air take up space designated for hot water, preventing proper circulation.

Thermostat not working

The issue may be that the thermostat at the bottom of the radiator is not working properly.

This is not unusual in cases where a higher temperature has been selected as this can cause the valves to seize in a closed state.

Sludge, debris, or blockages

On rare occasions, a radiator may be cold at the bottom and warm at the top. This is often because debris or sludge has accumulated in the system. This makes it hard for hot water to circulate.

A radiator leak

In the case of a radiator leak, you may have to replace the unit altogether. However, in some cases, you may be able to use external sealers or leak sealers to fix this depending on the extent of the problem.

Diverter valve fault

If the controls are working correctly and the pressure is correct, there could be an issue with the diverter valves.

This is a motorised valve in the boiler that controls the flow of warm water to either your heating or taps.

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An issue with the central heating controls

While this issue is rare, a problem with the central heating controls can occur, impacting the timing of your central heating and the signals to your boiler.

To see if this is the issue, you should check that your timing control is set correctly. Choose the ‘on’ demand to make sure that it heats your radiators.

The boiler pressure is too low

Combi boilers work on a closed-loop system and are pressurised between one and two bars.

If it is not properly pressurised, the boiler will not provide hot water to heat your home.

You can find out what the pressure is via the head of the cylinder, which tends to be located in the airing cupboard or by looking at the front of the boiler.

For more serious issues with your radiators and boiler, you should contact a professional.