Working principle: 1) Many-tubes-connected makes the solar collector system 2) The project is composed of solar collector, water storage tank, auxiliary heating system, computerized controller, pipe cycling system and other relative system 3) When the discrepant temperature of the solar collector and water tank reaches the set value, the controller shall start the circulation pump automatically and take the heat to the water tank 5) In case the temperature of the water tank does not reach the set temperature such as in cloudy or rainy days, the water system will start the auxiliary heating device automatically