... Heat Pipe Solar Collector Spec.(mm) Φ47×1500 Φ58×1800 Tube (pcs) 12 / 15 /18 / 20 / 25 / 30 Vacuum Tube Borosilicate glass, red copper heat pipe, aluminum fin ... solar water heater composes of heat pipe solar collector, storage water tank, workstation system, related accessories and interconnecting pieces, etc.Heat Pipe Solar Collector:1) Heat pipe solar collector for thermal collection, with ...