... :ISO9001,ISO14001,CCC,CE,Solar Keymark solar water heater:heat pipe tube pressure:pressuriz solar water heater: material:1.volume of storage tank:120L ... -target tube,high boron and silicon,content 3.3,structure,gradual change SS-AL-Nx/Cu,selective absorption coating5. ... completely automatic if connect with intelligent controller.2.Simple structure,easy plug-in installation,can be installed both in ...