... -pressurized solar water heater The CN-YS02 type has the stainless shell,so it can be used in the rain area Manufacturer non-pressurized solar water heater ... 1,vacuum tube length:47/1500mm,58/18002,vacuum tubes:15pcs,18pcs,20pcs,24pcs,30pcs3,Outer tank material:202stainless steel ... freely .it is suitable for the many residentbuildings. non-pressurized solar water heater