Working principle:

1. When the discrepant temperature of the solar collector and water tank reaches the set value, the controller shall start the circulation pump automatically.

2. If the discrepant temperature of the collector and water tank does not reach the set value, the circulation pump shall be shut automatically.

3. The circulation pump makes the heat-conducting liquid circulate automatically.

4. The heat-conducting liquid transfers heat to water by heat exchanger in the water tank.

5. In case the temperature of the water tank does not reach maximum, then start the auxiliary heating device.