Water heater system 1.EN12975 solar keymark 2.Anti-freezen & pressurized 3 ... tank temperature gets to the set value, the circulation system will start work. It will transmit the solar energy ... Vacuum Degree,P<=5*10-4,Service Life,10 years Mounting FrameAluminum Alloy,Thickness,1.8 mm, not have back ... (set)20102787763574022116916613613040HQ278213209172171Price(USD) Split heat pipe water heater system