Features: A: Water wouldnt run in the tube, so the heat delivery efficiency wouldnt be affected. B: It can be set at any angle required. C: Both for pressurized and non-pressurized one. D: The whole system would run normally if some of vacuum tubes broke. E: The whole system is connected without silica gel, so there is no problem of aging. F: The water is circulated with high efficiency by pumper. G: It can be for huge project by parallel or serial connection. H. On the special circumstance, because of balance of force, the copper pipe in the tube wouldnt distort.