Brazed plate heat exchangers in Geothermal Heating:

Geothermal heating uses up to 30% to 50% less electricity than the cooling system and conventional heating. It is the method used for heating buildings/spas by utilizing sources of hot water that exists already near the earth's surface. Usually, geothermal heat pump uses one electricity unit for extracting from the earth up to three units. This heating can help in improving humidity control as well by maintaining indoor humidity of about 50%, making these pumps helpful for humid climates. Such pumps are built on the basic principles of the regular heat pumps. The only difference is that rather than drawing heat from outdoor air the geothermal draws it from the earth, as it is thought to be even and stable. The geothermal heat pumps are not only restricted to heating, they are used for cooling as well water heaters. These pumps use land mass as a heat exchanger and is operated on the surface.

Many geothermal fluids used directly have numerous chemical species that can be harmful to conventional material of construction. This is the reason that the standard design practice for isolating the geothermal fluid from the system balance via using the heat exchanger. Brazed plate heat exchanger provides different advantages for geothermal heating that also includes their corrosion resistant materials availability such as the titanium, stainless steel, etc. at affordable price. The units are efficient and compact with rates of heat transfer three to ten times than those of tube and shell exchangers. Due to the simple construction of brazed plate heat exchanger, such units can be developed in small sizes, economically.

Due to the reduced cost, such exchangers can enhance the economics of geothermal systems and its small direct usage. These exchangers are manufactured by using together the heat transfer plates made from copper to braze. It differs from the common frame and plat exchangers in the way it is attached to the plate. The brazed plate eliminates the bolts, end plates and gaskets instead the plates are held together by brazing with copper.

Most of the geothermal fluid has ammonia copper, hydrogen sulphide and copper alloys that are usually not permitted in the construction of geothermal system. The condition differs in case of these exchangers because of the length and thickness of the brazed units. Exchanger limits the rates of application flow to about 100gpm. And the maximum area of heat transfer is limited to 200ft2.