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Heat Exchanger In A Boiler

What is a heat exchanger in a boiler?

As its name implies, a heat exchanger allows for two fluids or substances, usually water or gas, to exchange heat without mixing. Instead of combining them, the substances are kept separate because it is a far more efficient way of heating the water.

Inside the heat exchanger is a long, coiler pipe, which is surrounded by a cold substance, like water. A hot substance, either gas or water, is then fed through the pipe. As the hot substance moves, it gradually heats the nearby water.

Heat exchangers are typically found in boilers. Essentially, they encourage your boiler to heat the water, which is then sent through your radiators, to heat your home.

Heat exchangers can also be situated in other appliances. For example, they can be used to recycle heat in the waste gases at power plants, as well as to heat swimming pools. Heat exchangers can also work in the opposite way, to cool something down. Therefore, refrigerators and air-conditioners contain heat exchangers, to keep the heat away from the room or compartment to keep the temperature down.

What boilers have stainless steel heat exchangers?

A heat exchanger plays an important role within your boiler. Without one, your boiler would not be able to heat the water that travels around your home, leaving you with no hot water or heating.

Therefore, it is important to have a high-quality, reliable heat exchanger. A strong material that suits the functionality of a heat exchanger, is stainless steel. Due to its resistance to corrosion, a stainless steel heat exchanger is likely to last for longer. It will also help your boiler maintain a good level of efficiency, potentially allowing you to save money on your energy bills.

A heat exchanger made from stainless steel can withstand a higher flow rate than other materials. With more gas or water passing through at a faster rate, the water will be heated up quickly. This escalated water flow, also minimises the risk of blockages from debris or rust, increasing the lifespan of the heat exchanger.

Stainless steel is self-cleaning and a light material, making it ideal for use in a variety of appliances that require water to be heated.

How to clean a boiler heat exchanger

Even if your boiler’s heat exchanger is made from stainless steel, it will still need cleaning occasionally. This is because, over time, your might find your pipes have corroded slightly, leaving dirt and debris to clog up the system. If this is the case, then your heating system’s efficiency will suffer as a result. A clear indicator that this has happened, is if your radiators are cold in places when the heating is on.

To have your heat exchanger cleaned, you should contact a suitably qualified heating engineer, although, it is possible for them to do this during your boiler’s annual service. At first, the engineer will locate the heat exchanger, before applying water at a high pressure to remove any dirt or debris. You should make sure that your heat exchanger is cleaned every 12 months, to keep your boiler working at its maximum efficiency for longer.

Worcester Bosch Boiler

Homeowners are still able to get a FREE boiler grant or insulation grant via the ECO scheme, which is still available to households that qualify. Warma UK are currently working throughout the UK helping privately owned and rented homes to improve home energy efficiency and save money on rising energy bills.

For more information email –

Or call 03304600065

Apply For Your Government Backed Heating Grant

Following your successful application, we will arrange a free, no obligation survey to ensure the maximum grant is obtained and advise you on the best products to reduce your homes energy usage.

Michael Cornish