Figure out what you need from a heat exchanger and choose the right vendor
By W. Aiman Mueller
Heat exchangers, also called heat transfers, transfer heat from one substance to another. Usually, but not always, the two substances are separated by a wall. Thermodynamics and material characteristics combine to either transfer heat by dissipation or absorption. A common example of this is a car radiator, which cools antifreeze by transferring heat to the surrounding air.
Heat exchangers have multiple commercial uses. For instance, they are used in water heaters and air conditioners. However, there are also many applications for industrial heat exchangers. Examples here include large boilers or HVAC units. Industrial heat exchangers are also used to redirect heat that would otherwise be wasted.
Below are some of the types of heat exchangers:
1. A coaxial heat exchanger is highly efficient and works well in tight spaces, especially in water-run equipment.
2. A brazed plate heat exchanger is excellent for hydraulic systems, but also has various commercial applications, like swimming pools. It has a turbulent flow that reduces deposits of impurities.
3. Ceramic heat exchangers feature high-efficiency, low-pressure loss.
4. Shell and tube heat exchangers can handle abrasive materials.
The best contacts and resources to help you get it done
Buy from the right heat exchanger manufacturers
The heat exchanger industry is broad, so there a lot of sources to choose from. Make sure you find a vendor that either offers a wide range of units that cover an equally wide range of applications, or shop a source that's specific to your needs. Limiting yourself to a source that sells only a few heat exchangers could mean you end up buying a unit that's less than ideal for your situation.
I recommend: Doucette Industries, Inc. has a tremendous selection of chillers and specialty heat exchangers. API Heat Transfer is a large, experienced company that delivers quality solutions for industrial applications.
Find your way around the heat exchanger industry
If you haven't purchased a heat exchanger before, you might not know which design is best for you. If you're not sure if a coaxial heat exchanger would be best, or if you should look for ceramic heat exchangers, there are some quick ways get yourself pointed in the right direction.
I recommend: Heat Exchangers Online has a user-friendly website full of information to help the consumer understand how their products work and what they're used for. They carry a fairly wide range of products, including air heat exchangers and various models for swimming pools. Lytron also has a great deal of information on the products they offer. Check out these companies first to do some fast, effective research.
Maintain and repair your heat exchanger
Heat exchangers usually have two materials flowing through them. The flow of these materials is parallel, or they flow perpendicularly to one another. In any case, the flow leaves residue that sometimes results in leaks and/or lowered efficiency. In some cases, there is also the possibility of biofouling, the result of microorganism growth. Using river water for cooling often results in biofouling.
I recommend: Rolan Plant Services, Inc. offers a wide range of industrial cleaning services, including hydro-blasting and chemical cleaning. Hennigan Engineering is another industrial choice; they even handle nuclear plants. When servicing commercial heat exchangers, pay close attention to the manufacturer's literature.
Tips & Tactics
Helpful advice for making the most of this Guide
To test the maintenance condition of your heat exchanger without dismantling it, use an eddy current method.