Steel vs. aluminium in radiator manufacture – is there a conflict?
The simple answer and the quick one, is not really. And the same is true of any other metal they can be made of – it’s not really an issue. At the lowest point of commonality, when 1000 BTUs of heat go into a radiator – whatever metal it’s manufactured from – mild steel, stainless steel, aluminium, brass, copper or cast iron – you can only get a maximum of 1000 BTUs out. Nothing more and nothing less.
The vast majority of radiators manufactured for the UK and Ireland marketplace are made from mild steel – well in excess of 99% of them in fact, and as is the case with much of current manufacturing industry, the cost of starting a brand new manufacturing plant to produce a sufficient quantity of radiators using alternative metals to have any impact on what is a very established sector, would be hugely expensive to the point of not being a viable or credible option. There will always be smaller manufacturers who attempt to develop a niche market for themselves providing products made from alternative materials, and that is certainly the case in the radiator marketplace. But the sheer volume of mild steel panel radiators being produced, and actively required by the mainstream new build and replacement marketplaces will ensure that mild steel will remain the dominant – and by far the most dominant – material for radiators for the foreseeable future. The requirements of architects and building designers for the occasional alternative for ‘one off’, even if high profile building, where the budget exists to allow for alternative material based products to be specified, will never match the huge day to day demand for mild steel radiators that have proven performance, asthetics and rapid availability as part of their constant appeal.
Even if you ignore this premise, and assume the demand for alternative products existed at a high level of demand there are benefits and issues with using each alternative metal. Looking more closely at aluminium, whilst heat up time for aluminium radiators is certainly quicker than for mild steel radiators, cooling also happens more rapidly. Steel panel heat up is slower but the heat capacity of mild steel is better – the so called ‘stove effect’, and cooling occurs more slowly which allows for residual heat to remain in the property and the rooms being heated, for longer, with a more gradual reduction in heat.
On the manufacturing front, aluminium radiators manufacturing process is by a die casting method and or extrusion, which is simple enough. However as suggested already, the production scale is small currently so capacity for production is low. The manufacturing process of aluminium radiators is necessarily manual, which increases the risk of quality issues when installed and the manufacturing process requires sanding to remove blemishes on the face of radiators – something not required by steel panel radiator manufacturing process.
In operation, aluminium radiators without integrated steel tubes can see reduced life span due to galvanic corrosion that occurs when aluminium is combined with other metals in a heating system, the metal that is most anodic – that is, with a lower galvanic potential – will corrode- aluminium in this case.
The heating industry in the UK and Ireland has happily accepted that mild steel radiators, make a huge amount of sense as they are easily and widely available, and they offer a history of excellent performance. Modern manufacturing methods ensure huge reliability and repeatability and the ability to develop a wide range of aesthetically pleasing designer and decorative radiator designs to complement the traditional steel panel radiators which in themselves have developed better looks with rounded edges, integrated panels and grills.
The larger manufacturers have a large share of the overall market share and can happily meet the demand of specifiers and installers across the UK and Ireland, allowing smaller operators to develop their niche products and supply their products to those minority of specifiers who want to incorporate alternative metal radiators, for whatever reasons.
Steel v Aluminium? It’s not an irrelevant question, but the reality of the market place makes it less important than it might at first seem. There are many realities of mass manufacture that need to be addressed and accepted and the decision that has been made over the years for mild steel to be the metal of choice, seems here to stay.« Back