Product Description

In nonpressurized system, cold water in storage tank flows downward into the glass vacuum tubes, and there it is heated with the solar energy absorbed with the coating sputtered on inner tubes, and when cold water in glass tubes becomes hot, it rises upward back to storage tank because of the larger proportion, how much hot water rises upward to the top of storage tank, how much cold water will flow downward into glass vacuum tubes at the same time, hence the circulation presents in the nonpressurized system.