Preface.
According to the relevant media reports, China's flat panel solar water heater in 2009 only 10% of market share, cast bronze while the vacuum tube water heater is the mainstream market. The contrast with China, Europe and other developed countries is based on the solar water heater market, flat products. China Rural Energy Industry Association Professional Committee of the utilization of solar energy Luo Zhentao said: Foreign commonly used solar water heater, bronze bushing first, because of foreign pressure plate solar water heater, long life, easy to form the secondary loop system, the second is easy with the building combination, easy to install and the third is the system safe and reliable. With the rapid development of urbanization and land resource constraints, high-rise residential buildings has become the main form. dry bushing Can be used as high-rise building area of less than the roof, solar water heater with a balcony-type or a brick wall-style has become an inevitable trend. Vacuum easily broken, easily leak sealing gasket aging, with a balcony or wall installation of security risk is relatively large. Flat-plate solar in all cases due to the outstanding performance, plain bearing will be re-entered the people's vision.
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