1.Solar water heater 2,High performance 3, Heat preservation:72hours we ... condenser, evaporator, heat pump,air cooler,air conditioner and solar water heater manufacturer in China, which has more than 15 years ... Vacuum tube: QB-AL-N/AL-47-1500/58-1800, coating: AL-N-AL or AL-SS-CU 6. Vent connection/electric heater ... tank diameter: 470mm for SS58system,420mm for SS47system Energy saving solar water heater