... -Freezing 4. Heat pipe in it. Product manufacture parameter tableProduct ModelXK-SPVacuum tube58-1800mm co-axial structure high borosilicate 3.3 three ... temperature ≥-35°CFrame optional angle0°,25°,38°,45°Capacity of water tank80L,100L,150K,200L,250L,300L,400L,500L. 40L/person ... .Please ask the information from our sales men. Split Pressure Solar Water Heater