Tube-in-shell heat exchangers are generally constructed from 316L stainless steel offering extreme durability and protection from corrosion in DHW applications. Heat transfer is enhanced through low profile grooves rolled into the tubes that create moderate turbulence on shell side without the problematic mineral deposition often found in finned units. In residential DHW applications the B-150 is idea supporting systems with up to 66 ft2 of collector area. The table below lists the tube in shell units, their dimensions and the maximum DHW array area they can support while maintaining performance.
These heat exchangers are also well suited for residential solar pool and spa applications. The design of these heat exchangers allows them to be placed in-line on the pool filtration circuit unlike plate heat exchangers which usually require a branch arrangement. The standard tube in shell unit is constructed of 316L stainless steel, which has excellent corrosion resistance to chlorinated pool water provided the chemical balance and pH of the pool water is closely regulated. Titanium heat exchangers have superior chemical resistance and are required for salt water pools and spas. The table below lists the heat exchanger units sized for pool applications and the maximum pool array area they can support while maintaining performance.
Heat Exchanger Sizing Recommendations
Tube heat exchangers are typically used as a sidearm style heat exchanger in retrofit applications. Conventional electric water heaters can be converted for use with solar by adding a tube heat exchanger. If the water heater is to be used to pre-heat a gas fired unit then it is suggested that the heating elements be removed from the electric water heater and the tube heat exchanger plumbed between the element holes for optimal performance. If the water heater is to used as the auxiliary electric heater, then the tube heat exchanger may be plumbed between the drain and a tee placed on the hot water outlet leaving the elements intact. In either scenario, a second pump may be placed in the potable water line for increased performance.