... CE 10 years warranty OEM service Non-pressure Evacuated Tube Solar Geysers Water HeaterBrief Introduction of solar geysers ... 420/460/470mm2) Inner tank diameter: 310/360mm3) Vacuum tube counts: 15, 16, 18, 20, 22, 24, ... 26, 28, 304) Tube size: Φ47x 1, 500mm, φ58 x 1, 800mm5) ... ) Insulation: 50/55mm polyurethane Non-pressure Evacuated Tube Solar Geysers Water Heater for Apartment