... heat exchanger, condenser, evaporator, heat pump,air cooler,air conditioner and solar water heater manufacturer in China, which has more ... Outer tank diameter: 470mm for ZXJ-58 system, 420mm for ZXJ-47 system Non-pressurized Collectors Specification: 1. Insulation layer: ... steel plate 6. Swimming pool, hotel etc. hot water project using rooftop unpressurized solar hot water system made in china