1). testing for EN12975 certification 2). -30 degree is ok 3). easy installation 4). absorber area efficiency more than 80% Features:1) Reliable and efficient twin-glass solar tubes 2) Copper heat pipes for rapid heat transfer 3) Easy plug-in installation 4) Free maintenance 5) Suitable for mains pressure water 6) Corrosion resistant silver brazed copper header 7) The surface is made of powder coated galvanized steel8) Stable solar conversion during the day9) The perfect solar collector for domestic solar water heater systems 10) Ideal for commercial solar water heating applications How it works: 1) The operation of the solar collector is very simple.2) Solar absorption: solar radiation is absorbed by the solar tubes and converted into heat.3) Solar heat transfer: heat pipes conduct the heat from within the solar tube up to the header pipe4) Solar energy storage: water is circulated through the header, via intermittent pump cycling. Each time the water circulates through the header, the temperatures is raised by 5-10°C. Throughout the day, the water in the tank is gradually heated

Heat pipe solar collector (R4 series)