This invention relates to a heat exchange assembly and concerns the configuration and nature of heat exchange elements within such an assembly to optimize efficiency.
Heat exchangers are used in a number of different applications. These include use in heaters having application in domestic and industrial situations. Heat exchangers have commonly been used in central heating apparatus in which air to be heated and diverted to one or more room outlets is blown through the heat exchange assembly and the present invention has been developed primarily for this application. However, the present invention is not limited to such use.
A heat exchanger is a device that transfers heat from one fluid to another without allowing the fluids to come into contact with each other. The fluid being heated in the case of a central heater is of course ambient air. The efficiency of a heat exchanger is generally enhanced if the fluid to which heat is to be transferred passes through the heat exchanger in the opposite direction to the direction of the fluid transferring heat. Such an arrangement is known as counter-current heat exchange. Counter-current heat exchange is generally more efficient than co-current heat exchange due to the maintenance of a greater temperature differential between the two respective fluids along the length of the heat exchanger.
This concept has been adopted in the past in the design of central heating apparatus but has required the use of large and cumbersome assemblies for the enclosure of the heat exchange elements. The size of such assemblies has made underfloor and roof installation difficult and in some cases not possible.
An object of the present invention is to provide an improved heat exchange assembly which is thermodynamically efficient. It is a further object of the invention to provide a heat exchange assembly which is compact.