... pressure solar water heater 1.For 5years warranty 2.CE,CCC,ISO,approved 3.OEM is welcomed 4.Sample offer (OEM)Non pressure solar water ... heaterWorking Principle: Parameter:1. Water tank inner shell: 0.4~0.5mm SUS304 ... steel with painting,or Aluminium alloy, or stainless steel.4. Water tank heat insulation layer: 50~60 mm polyurethane foam.5 ...