... solar collector, Hot Water Heater, solar hot water, Solar Water Heaters, solar energy heater, Solar Energy Water Heater, Solar Heat Collector, Hot Collector, Solar Water, pressuried solar heater, Solar ... operation 5) Anti-freeze: No water inside the tubes when it works 6) The system controller has ... 58 x 1, 800mm b) Qty: 10 /15 / 20 / 25 / 30PCS * Temperature insulation layer 50mm thickness imported ...