Heat exchangers function on similar theories of heat transfer whether in a laboratory or a domestic situation. When considering efficiency, always look at the construction materials and design of a manufacturer's product and inquire as to warranties.
The efficiency of a heat exchanger is related to how well it transfers heat through a stream from one location or device to another. This stream can be composed of various elements including liquid and gas. Chemical Engineer Resources describes this efficiency as "the ratio of the actual amount of heat transferred to the maximum possible amount of heat transferred with an infinite area."
There are three basic types of exchanger: the parallel, cross and counter flow. However, there can be differences within designs for specific stream content as well. For example, fluid transfer designs can have three varied heating or cooling methods with either external utilities or an alternative processing stream.
With regard to efficiency or effectiveness, there are drawbacks as well as benefits to each form of exchanger design. The counter flow exchanger is most efficient as it optimises the average heat transfer over the greatest surface area.
Domestic heat exchangers can be used to enhance solar power potential, distribute heat through flooring and rid your roof of snow accumulation. Among various models, some even allow for a wood-burning stove unit to provide the original heat source.