What is a Heat Exchanger and How Does is Work?

Heat Exchanger in Puyallup, WA

Most homeowners usually take the functions of furnaces and boilers for granted until something goes terribly wrong. When these appliances are in good working condition, it can be quite easy to forget the components that allow them to do this. Most people are unaware that the heat exchanger is basically the most important part of boilers and furnaces.

So, what exactly is a heat exchanger and what does it do? Read on to find out!

What Is a Heat Exchanger?

A heat exchanger is basically a device that facilitates the transfer of heat between two or more fluids. This usually takes place without letting the two fluids mix together. It is important to note that heat exchangers can be found in all sorts of appliances and industries. For instance, you can find heat exchangers in power plants being used to recycle heat in the waste gases or being used to heat swimming pools.

Additionally, heat exchangers can also function in the opposite way. Heat exchangers can also be used in air conditioners and refrigerators to draw heat from mediums and keep compartments cool.

How Does a Heat Exchanger Work?

When your boiler or furnace is ignited and starts burning natural gas or even propane fuel, its combustion by-products, also referred to as flue gases enter and travel through the heat exchanger. The heat exchanger is usually fitted with a long coiled pipe. The hot flue gases afterward heat the coiled pipe as the gases make their way to the exhaust outlet of the boiler or furnace.

While this is happening, the hot coiled pipe then heats the cold air or water surrounding it. A heat exchanger has to be used to prevent the two substances from mixing, or else your furnace or boiler wouldn’t work as efficiently as required.

Types of Heat Exchangers

Even though all heat exchangers serve the same purpose, they usually work in different ways. This explains why there are different kinds of heat exchangers. Here are the different types of heat exchangers based on heat transfer.

Plate Heat Exchangers

Plate heat exchangers are heat exchangers that transfer heat from one medium to another using thin metal plates made from stainless steel or titanium. These metal plates are usually held together by a fine clearance which is maintained together by the gasket material of asbestos fiber and rubber.

Since these plates occupy a small area while creating a large surface area, these heat exchangers tend to be compact. This type of arrangement is very popular with heat exchangers that use air or gas and low-velocity fluid flow.

A good example of this heat exchanger is usually found in an internal combustion engine where an engine coolant flows through radiator coils as air flows past the coils. This ends up cooling the coolant and heats the incoming air. Compared to other types of heat exchangers, plate heat exchangers have lower volume and cost.

Double Pipe Heat Exchangers

Double pipe heat exchangers are very cheap in terms of design and maintenance. This characteristic makes them ideal for small industries. In these heat exchangers, the heat exchange process takes place by one fluid flowing inside the tube while the other flows on the outside. Even though these heat exchangers are cheap and simple, they have low efficiency. This has made modern industries opt for more efficient heat exchangers like shell and tube.

Shell and Tube Heat Exchangers

Shell and tube heat exchangers are undoubtedly the most commonly used heat exchangers in the industry. Additionally, shell and tube heat exchangers are further categorized based on the number of shells and tube passes involved.

It’s important to note that shell and tube heat exchangers are mostly used for high-pressure applications with pressures above 30 bar and temperatures exceeding 260ºC. This is attributed to the fact that these heat exchangers can withstand high pressures due to their shape.

How to Enhance the Efficiency of a Heat Exchanger


As a homeowner, it’s important to understand that the installation of a heat exchanger matters a lot. If you reside in Puyallup, WA, ensure that you hire a reputed company like Puyallup Heating & Air Conditioning to install your heat exchanger.

Flow Rate

In order to enhance the efficiency of the heat exchanger, you need to ensure that both the primary and secondary sides of the appliance are balanced.

Temperature Differential

The performance of the heat exchanger also depends on the temperature difference between the hot fluid and coolant. In order to enhance the efficiency of the heat exchanger, the coolant needs to be cooler than the hot fluid.

Are you looking for a reputable heating and cooling company in the Puyallup area to install your heating systems? Contact us today at Puyallup Heating & Air Conditioning and let us take care of all your heating and cooling needs, like repair, maintenance and installation.