Did you know that around one-fifth of all UK boilers break down each and every year? The culprit, in many cases, is sludge. While a typical lifespan of a boiler is between five and ten years, if sludge is removed, it will last even longer!
So, What Exactly is ‘Sludge’?
It’s basically ‘dirty water’ which is created when flowing around your heating system. On the way, water reacts with rust (iron oxide) forming a black, gooey liquid. It wreaks havoc on your heating system, causing pipe blockages and cold or patchy heat in radiators. In other circumstances, it causes untold damage on expensive components like the heat exchanger on your boiler which heating engineers would charge a fortune to replace. Blocked radiator valves are another common result of sludge buildup. Water flow becomes restricted, despite the pump working at the same rate, which can blow a seal, cause a leak and corrode parts like the PCB.
How to Know if You Have Sludge Buildup
There are lots of potential signs to look out for. Including:
- Unevenly distributed heat on a radiator, or no heat at all
- Having to always ‘bleed’ radiators
- Your boiler making bizarre noises
- Radiator valves being turned up but not reaching the right temperature
- The pump being at too high pressure, overheating or blowing a seal
- Hot pipework to the radiator, but the actual radiator being cold
- Damaged or broken boiler parts
- Hot boiler flow but a cold return valve
- Valves that constantly break and require replacing
How to Check for Sludge Buildup in Your System
There is a way to work out whether sludge exists in your system without having to dismantle it entirely.
Firstly, place a container under the valve, then drain it with a key. Examine the water in the container. Is it discoloured? If so, sludge exists in your system. Sludge, in itself, isn’t exactly problematic. However, if your radiator is not reaching the right temperature, or is cold, the issue needs addressing.
Bleed all the radiators in your home, then set the temperature of your heating to the maximum level. Once again, check each radiator as well as the pipes that feed them. If they are warm, sludge is probably causing the blockage there.
I am having a New Boiler Installed. Do I Need to Clear the System of Sludge?
In short, yes. Sludge restricts the flow through the system, adding pressure to components in the boiler and eventually wearing them out. It’s possible the sludge itself can ruin certain parts, such as the heat exchanger, and this is expensive to replace. Not to mention particles of rust and dirt which can lower life expectancy of various components.
How to Stop Sludge Buildup
You have two main options when it comes to stopping sludge buildup in your central heating system. These include:
- Scale Reducer. Being important in hard water areas, this device, which costs around £100, can protect an entire heating system from sludge.
- Magnetic Sludge System Filter. This catches particles in sludge as the water circulates around the system, making it less likely to form blockages elsewhere.
Regardless of which option you choose, make sure you choose a quality brand. Also, add inhibitor to your system, which breaks down the particles that otherwise collect at the bottom of radiators.
How to Remove Sludge from your Heating System
In addition to the other methods, you might want to try either flushing your system or replacing some of your radiators.
Manual Flushing. This involves removing radiators and flushing out the sludge with a hose pipe. Although it won’t get rid of all the muck, it will clear most of it. You can opt to do the job yourself which will take about a day, or get in a heating engineer to do it. Expect to pay between £150 and £300.
Power Flushing. Similar to a manual flush, this is where a heating engineer uses a machine to flush your radiators out at a high flow rate. It’s better at clearing out the stubborn sludge that won’t shift in a manual flush. However, care will need to be taken not to damage old components.
Radiator Replacement. If you find a couple of your radiators aren’t working, it might save you money to just replace them with new ones. Plus, because they’re more efficient than older radiators, they’ll help save you money, and keep your house warmer!