Central heating systems need to be serviced annually for many reasons, and one of them is saving money. Your system could be costing you more money than it should because it is not running efficiently.

Signs of a problem with your heating system

Are you noticing that your radiators are not as hot as they once were? You might have turned up the thermostat on the boiler to increase the heat output to no avail. Perhaps you notice that there are cool spots on the radiator, particularly that they’re cold at the top and hot at the bottom? Bleeding the radiator ( releasing air trapped inside the radiator) makes no difference and, in fact, there is no air to release. Perhaps your pump has failed or other boiler parts are needing replaced and the water inside the system looks black and dirty or maybe your energy bills have increased? Your heating system may also be noisy, making a gurgling, clanking sound known as “kettling”. These are all signs that your radiators may be full of sludge and that your heating system isn’t working efficiently, with water struggling to move around as it should do. If you experience these tell-tale signs then your central heating system possibly needs cleaned in order to restore it to optimal health.

What causes sludge to form?

All heating systems are at risk from Magnetite, commonly referred to as sludge. This is a black substance comprised of dissolved, rusted metal from the pipework in your heating system. It forms when air and water react with ferrous components – for instance, the water within the system reacts with the steel inside your radiators. If left to build up, it can have devastating effects to the boiler and the system.

Effects of sludge on your central heating system

Left untreated, sludge will very likely affect the water carrying components of your central heating system, i.e. pump, valves and main heat exchanger (the “engine” of your boiler). It causes damage to radiators and pipework and can eventually cause the entire system to grind to a halt, in the worst cases the entire system needs re-piped and/or the boiler replaced.

It will certainly affect the heat output of the system and lead to higher energy bills, up to 36% heat loss can occur due to sludge, resulting in a very inefficient heating system.

How can I get rid of the black sludge?

A power flush or power cleanse (depending on your type of heating system), is a process of cleaning the sludge out of the central heating system restoring it to full health again. Specialised machines and magnets are used to flush water through the pipework and radiators in order to force out the sludge. This should be undertaken by qualified heating engineers so that no damage occurs to your central heating system.

Afterwards, fitting a magnetic filter will prevent the build-up of further sludge. This will be cleaned out at the same time as your boiler servicing each year to keep the system in good shape.

Prevention is always better than cure so it makes sense to have your boiler serviced annually in order to pick up on issues before they become a problem,