Plate Heat Exchangers
SunEarth offers plate & frame heat exchangers for efficient solar heating applications. Our copper brazed plate heat exchangers are constructed entirely from 316L stainless steel. The individual plates with the unit are embossed with a chevron pattern that creates a lattice of interwoven flow channels promoting turbulence.
Turbulence dramatically improves heat transfer rates while reducing deposits within the unit. The versatility of brazed plate heat exchangers allows over 200 FT2 of heat transfer surface area in a unit that has a foot print of 1.2 ft2.
Brazed plate heat exchangers are available in single and double wall configurations.
The small footprint of our brazed plate heat exchangers makes is economical to obtain heat transfer in indirect systems that are comparable to direct system designs. Our brazed plate heat exchangers are available in a range of sizes allowing for optimal balancing of heat transfer capability and pressure loss.
Units are available in 10 plate increments and come standard with male NPT fittings (sweat fittings may be custom ordered).
Heat Exchanger Sizing Recommendations
Typical Applications: Our brazed plate heat exchangers are typically used in double pumped configurations for glycol and drainback systems. Our brazed plate heat exchangers offer higher performance and typically lower cost than immersed tube bundles for commercial scale systems. Although the requirement of a potable side pump adds to the mechanical complexity, our brazed plate head exchangers can boost collector output by 10-15% over immersed bundles by allowing the collector to run at the lowest possible temperature differential. The increased output usually can outweigh the added cost and complexity of a second pump in most installations.
Sizing Brazed Plate Heat Exchangers for Commercial Systems
Sizing of the heat exchanger is critical to overall system performance. If the heat exchanger is undersized then the operating temperature of the collector loop will rise thus lowering the array efficiency. Alternatively oversizing a heat exchanger leads to added system cost with little added benefit. The figure to the left shows how the solar fraction of a typical commercial system is affected by the effectiveness of the heat exchanger. An effectiveness of 1.0 represents 100% efficient heat transfer. Brazed plate heat exchanger sizing guidelines are based upon an effectiveness of 070-0.80 that provides the optimum balance between system efficiency and unit cost. With effectiveness in this region the overall solar fraction is only 2-4% less than that of an equivalent direct system.
Sizing Example: Array of 24 EP-40 Collectors
At 40.9 ft2 gross area per collector, 24 EP-40 collectors have a total array area of 979.2 ft2. Referencing the brazed plate heat exchanger table above, we would select an SP110Y-30 for a single wall application or a SP110DW-30 for a double wall application. Once the heat exchanger is known the Cv value can be used to find the pressure drop imparted by the heat exchanger for pump selection as well as the HX volume for fluid domain calculations.