... Vacuumm tube heat pipe solar heating collector 1.OEM provide 2.SOLAR KEYMARK,SRCC,CE 3.Antifreezing -40 degree Canada Vacuumm tube heat pipe solar heating ... full system completely autumatic, you can uae hot water anytime, high efficient,and no-pollution.3. Installation ... 0mmHeat Pipe Evacuated TubeVacuum TubeThree high vacuum tube, ALN/ALN-SS/CU absorber coating, Dia: 58mm, Length: 1800mm.Copper Heat ...