What is a heat exchanger in a boiler?
The purpose of the heat exchanger in your boiler is to transfer the heat produced from gas into water. This hot water then moves through the pipework and into your radiators. To put it simply, a heat exchanger is the most important component in the boiler. In a lot of ways, a heat exchanger’s role is similar to the engine that’s inside your car!
Hopefully with this explanation you’ll have a better idea of what a heat exchanger is.
In the following article, you’ll see examples of heat exchangers used by boiler manufacturers that are currently operating and selling in the UK. You’ll also learn about which materials allow for a longer lifespan.
For further information, you can read detailed comparisons of several brands in the heating arena:
Types of Heat Exchangers in your Boiler
Heat exchangers can vary in appearance, but materials also need to be considered. Most will either be aluminium or stainless steel, but stainless steel has much better corrosion resistance, so your boiler is better protected.
For aluminium heat exchangers, there are also disadvantages that come with it. While they initially have strong thermal conductivity (heat transfer), they are more prone to corrosion from magnetite sludge and other chemicals incorrectly added to the system. As well as this, they cannot be used with softened water.
REMEMBER: Based on the above information, any damage to the heat exchanger may cause your warranty to be void. As a result, the manufacturer may decide not to replace the component.
Which Material is Best?
In order to compare UK-based manufacturers, it’s good to know what material is used for the heat exchangers.
In the following table, you can see the benefits that each material provides, giving you a much better idea of what a high quality boiler should be:
Who has the best heat exchanger?
As you can see from the table, there’s quite a difference with how each manufacturer uses materials for their heat exchanger. However, simply claiming that ‘stainless steel is the best’ isn’t enough. You also need to know if the steel from one manufacturer is better than another.
Manufacturers such as Vaillant or Baxi may very well offer stainless steel for some of their boilers, but a low grade material still won’t give your boiler the longevity you’re looking for if the quality isn’t high enough.
As you can see from the table, there are a few differences in the materials, but simply claiming that ‘stainless steel is the best’ isn’t enough. You also need to know why.
Some of the brands listed provide boilers with aluminium OR stainless steel, but there’s only one manufacturer among them that uses a superior stainless steel consistently across their entire boiler range, and that’s Viessmann.
Accepting only top quality materials, the stainless steel used for the Viessmann boiler range is only one grade down from surgical steel, making it an easy choice for people that a want a boiler designed with the customer in mind that can provide excellent efficiency.