If you have a ‘wet’ central heating system (with radiators full of water), it is common for there to be some strange noises, like knocking, clicking or banging.
Sometimes this is because of the metal expanding as it gets hot. Other times, it is because there is some air in the radiators. This will not only cause some strange noises, it will also stop your radiators warming up. Feel your radiator when the heating is on – is it cold at the top, but hot at the bottom? This means air is trapped inside.
To fix it, you will need to ‘bleed’ the radiator using a special radiator key (you can buy them cheaply from hardware stores). You will also need an old cloth.
There are many videos on YouTube that show how to bleed the air from a radiator. It only takes a few minutes.
Usually, you need to bleed the radiators once a year. If you need to do it more often, there might be a leak somewhere – ask a plumber to check it out.