Aluminum radiators are increasingly seen as an alternative to the steel and cast iron radiators with which we are more familiar. However, as a relatively new offering in the UK, radiator retailers are often asked the following questions:

• What are the benefits of aluminum radiators?

• What is the difference between aluminum and steel or cast iron radiators?

• Is there anything I need to keep in mind when buying aluminum radiators?

The benefits of using aluminum to make radiators

The physical properties of aluminum make it a perfect material to build a radiator. It offers the following positive features:

• Recyclable – Since aluminum can be easily reworked, recycled aluminum is widely used in everyday products, including radiators;

• Economical: the use of recycled aluminum keeps production costs low;

• Lightweight: this makes transport and installation easier and consequently cheaper;

• Long warranty periods – aluminum radiators come with warranties of up to 10 years as this material has a protective surface oxide film that makes it naturally resistant to corrosion, although other inputs can cause a risk of corrosion. See below for more information *;

• Quick to react or “thermally conductive”: aluminum ensures rapid heat transfer from the water inside the radiator to the room air. In practical terms, this means that radiators should only be turned on just before the room is needed. On the other hand, aluminum cools just as quickly as cast iron, which retains heat for hours.

• Variety of shapes and styles – Aluminum is relatively smooth, yet durable and has high “ductile strength”, meaning it can be stretched or “extruded” into long strips. Therefore, aluminum is often used in vertical radiator models and is commonly used for contemporary style “feature radiators”; and

• “Sectional” options: The “extrusion” process means that sections can be formed evenly and radiators can be of “sectional” construction. An aluminum sectional radiator is assembled by joining any number of sections to create the desired width; This allows for a wide selection of widths and means that radiators can be easily sized to fit existing pipes. The same sectional construction method is used for cast iron and some steel radiators. The reach of the large radiators means that large heat outputs can be achieved.

 

Comparison of aluminum with steel and cast iron

There is no one material that is better than the other; there are pros and cons to each. Your choice will depend on your particular circumstances and specifications.

• Price: There is a misconception that the cost of a radiator depends entirely on the material it is made from, but there are many other factors at play.

• Weight – Aluminum is light, while cast iron is heavy, and steel is somewhere in between.

• Warranty periods: Aluminum radiators typically carry a 10-year manufacturer’s warranty, but so do cast iron radiators. Steel tends to come in less than 5 years as steel is more prone to corrosion, although if the radiator is installed and maintained properly this shouldn’t be a problem.

• Reaction rate: aluminum heats up quickly, but then cools quickly, whereas cast iron takes longer to heat up and retains heat longer after shutdown. Steel is somewhere in the middle.

• Shapes and sizes: aluminum is relatively more ductile and malleable than steel and cast iron.

* Prevention against corrosion

To fulfill your radiator warranty, your radiator must be installed in accordance with BS5449, section five commissioning, which is a process that your installer must be fully aware of. This means that after installation is complete, the system must be properly flushed and filled to remove debris and minimize the presence of solid particles and chemical residues that can cause corrosion and damage within the system.

Any radiator (except those for a secondary hot water system) must be used in conjunction with a suitable corrosion inhibitor.

The corrosion inhibitor should be used in accordance with the manufacturer’s instructions and recommendations and should take into account the particular metals within the system. Corrosion inhibitors are available at most plumber and DIY stores.

For more information on aluminum radiators, contact a radiator specialist.