... freezen&Pressurized 3. CE, SRCC, Solar keymar Constant Temperature Air Source Heat Pump WaterHeater Pressurized Solar water heaters ... be used in all climates.3) Reliable and efficient with twin-glass solar tubes.4) ... method:We use silver welding between the top and tube body, so the connection part is ... But usually, their liquid has low efficiency and disappear very quick, usually one year later you ...