There are 25 vacuum tubes in each group of heater collection modules; The size of vacuum tube is 58 x 1, 800mm. A heater collection project is generally made of groups or dozens groups of heater collections by string or parallel linking. The hot water will be pumped to a big heat preservation water tank through a temperature cycle pump. The size of water tanks could be chose from 3 tons to dozens of tons based on customers' demands. The heater collection system as a whole need not be taken care by people. Once it is opened, there will be an immediate hot water. This type of heater collection is generally applicable to hotels, factories, hospitals, schools, swimming pools and other large high-capacity units using hot water.