... Simple structure and working principle CE,ISO9001,SGS,CCC OEM is OK Non-pressurized solar water heater, ... compactSimple structure and working principleCost-optimalCE,ISO9001,SGS,CCCOEM ... :Export carton with full foamsRemark:Diameter of solar water tank(mm):360/460Vent connection(inch): ... *1800) New Compact non-pressured solar water heater for 2013