Price Match Promise
Free, Fast Delivery
How to remove limescale from a heating system
Keeping on top of the limescale within your central heating system is really important for the longevity and efficiency of your heating system, especially in areas with hard water. If you've got a build-up of limescale, it narrows the pipework and restricts the amount of water that can flow around your system. You can compare this to the narrowing of arteries around a heart. This means that the components in your system are having to work much harder to compensate for the restricted hot water flow. In this article, we'll look at what limescale is, the implications it can have on your heating system and steps you can take to get rid of it.
Table of Contents
What is limescale?
The water in 'hard water' areas, such as London and much of the South East of England, contains a lot of minerals, a high proportion of which is calcium. When hard water dries, it leaves behind a calcium deposit - a white residue more familiarly known as limescale. If you live in a hard water area, you're likely to see evidence of limescale in kettles, around plug holes, or anywhere with a dripping tap. However, while these spots of limescale are very noticeable, you're unlikely to be aware of it happening inside your heating system until it starts to become problematic.
What problems can limescale cause?
The presence of limescale in your heating system can have several significant implications, affecting both efficiency and the longevity of your equipment. Understanding these implications can help you take proactive steps to address and prevent limescale build-up.
Inefficient heating
One of the most immediate impacts of limescale build-up is a loss in heating efficiency. Limescale acts as an insulating layer within your heating system’s pipes and components. This means that your boiler and other heating elements have to work harder to achieve the same level of heating. The extra effort required to push water through narrowed pipes and over insulating limescale deposits leads to increased energy consumption. This not only raises your energy bills but also contributes to a higher carbon footprint, making your heating system less environmentally friendly.
Increased wear and tear
As your boiler and pump work harder to circulate water through a limescale-clogged system, the increased strain can accelerate wear and tear on these components. This can result in a shorter lifespan for your boiler, pump, and other parts of the heating system. Over time, the added stress can lead to more frequent breakdowns and the need for costly repairs or even complete replacement of the boiler and other major components.
Overheating and damage
Limescale build-up can cause hot spots within your boiler and heating system, particularly if it's affecting your boiler's heat exchanger. These hot spots occur because the insulating properties of limescale prevent efficient heat transfer. As a result, the boiler can overheat, which can lead to a range of problems. Overheating can cause the metal components of your boiler to warp or crack, leading to leaks and potentially catastrophic failures. The consistent overheating and cooling cycles can also weaken seals and joints within the system, leading to further leaks and mechanical failures.
Uneven heating
As well as the danger of overheating, limescale can also cause uneven heating within your home. Radiators and other heating elements may not heat up uniformly, leading to cold spots and discomfort. This uneven heating is often due to blockages or restricted flow caused by limescale deposits, which prevent hot water from circulating properly throughout your system. As a result, some rooms may remain cold while others become excessively warm, making it difficult to maintain a comfortable and consistent indoor temperature.
Noisy operation
Limescale can cause your heating system to make unusual noises, such as tapping, whistling, or gurgling. These sounds are not just an annoyance, but they also an indication that there are underlying issues caused by limescale deposits. Noisy operation is often a sign that water flow is being obstructed, and that parts of your system are under strain. Ignoring these noises can lead to more severe problems down the line as the efficiency and reliability of your heating system continue to degrade.
Increased maintenance costs
Lots of limescale can mean that your heating system will require more frequent maintenance to keep it running smoothly. Regular descaling and cleaning are necessary to manage limescale build-up, and if the problem becomes severe, you may need to cal in a professional. The increased need for maintenance and potential repairs can add up over time, making limescale a costly issue to manage.
How can you remove limescale?
Effectively removing limescale from your heating system is crucial for maintaining its efficiency and longevity. Below we've listed some detailed methods to help you manage and eliminate limescale build-up.
Chemical descaler
Using a chemical descaler specifically designed for central heating systems is one of the most effective ways to dissolve limescale deposits. These chemicals are formulated to break down the calcium carbonate that makes up limescale. Here’s how to use a chemical descaler:
- Turn off the system - Make sure your heating system is turned off and cool before you begin.
- Add the descaler - Follow the manufacturer’s instructions to add the descaler to your system. This often involves introducing the chemical into the system via the filling loop or another access point, such as a heated towel rail, radiator or loft tank.
- Circulate the descaler - Allow the descaler to circulate through the system for the recommended time, usually a few hours. This helps ensure that the chemical reaches all areas where limescale might be present.
- Flush the system - After the descaler has done its job, flush the system thoroughly to remove any dissolved limescale and residual chemicals. This step is important to prevent any potential damage from leftover descaler.
- Refill and test - Refill your system with fresh water and test to make sure it’s operating correctly and efficiently.
Magnetic or electronic scale inhibitor
Installing a magnetic or electronic scale inhibitor is a preventive measure that can help reduce the formation of limescale. Below we've explained how these devices work and how you can install them in your home.
- Magnetic inhibitors - These devices alter the magnetic properties of the water, which changes the way minerals like calcium and magnesium crystallize, making it less likely for them to form limescale.
- Electronic inhibitors - These emit electric pulses that disrupt the formation of limescale by altering the electromagnetic properties of the water.
- Installation - These inhibitors are typically installed on the main water supply line entering your home. Professional installation is recommended to ensure they are correctly fitted and positioned for maximum effectiveness.
- Maintenance - Regularly check and clean these devices as per the manufacturer’s instructions to ensure they continue to function effectively.
A system filter
Installing a system filter can help capture debris and limescale fragments, preventing them from circulating and accumulating within your heating system. Here’s how system filters work and how to maintain them:
- Installation - System filters are installed in the pipework of your heating system, usually near the boiler. They capture particles as water circulates through the system.
- Maintenance - Regularly clean and maintain the filter as per the manufacturer’s guidelines to ensure it continues to effectively trap debris.
- Benefits - By removing debris and preventing limescale build-up, system filters help maintain the efficiency and longevity of your heating system.
Water softeners
Installing a water softener is an effective long-term solution for preventing limescale build-up by reducing the hardness of the water.
They use an ion exchange process to replace calcium and magnesium ions (which cause hardness) with sodium ions. This process softens the water, significantly reducing the potential for limescale formation. Water softeners tend to be installed at the point where the water supply enters your home. This ensures that all the water used in your heating system is softened. Regularly add salt to the water softener’s brine tank and perform periodic maintenance as recommended by the manufacturer to keep the system running efficiently.
Power flushing
Power flushing is a thorough and effective method for removing limescale and other debris from your heating system.
A powerful pump is connected to your heating system to circulate high-velocity, low-pressure water through the pipes and radiators. The water, often combined with chemical cleaning agents, dislodges and removes limescale, sludge, and other debris that has accumulated in the system.
This method not only removes existing limescale but also improves the overall efficiency and performance of your heating system. However, please note that power flushing is a complex process that should be carried out by a professional as improper handling can cause damage to your system.
Regular maintenance
Regular maintenance is key to preventing limescale build-up and ensuring your heating system operates efficiently. This should be something you get into the habit of regardless of limescale as it will help to minimise the chances of your heating system breaking down when you most need it. Below are some things you should keep on top of.
- Annual servicing - Have your boiler and heating system serviced annually by a qualified technician. This helps identify early signs of limescale build-up and address them promptly. Many boiler insurance policies actually insist on this.
- System checks - Regularly check your heating system for any signs of inefficiency or unusual noises, which can indicate limescale problems.
- Chemical Inhibitors - Consider adding chemical inhibitors to your system during regular maintenance to prevent limescale from forming.
